Document:

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                                                                    Exhibit 10.9

                                   AKSYS, LTD.

                     NOTICE OF TRANCHE B STOCK OPTION AWARD

     Grantee's Name and Address:      Howard J. Lewin
                                      6104 Kennedy Drive
                                      Chevy Chase, MD 20815

     You (the "Grantee") have been granted a Tranche B option (the "Option") to
purchase shares of Common Stock of Aksys, Ltd. (the "Company"), subject to the
terms and conditions of this Notice of Stock Option Award (the "Notice"), the
Stock Option Award Agreement (the "Option Agreement") attached hereto, and the
executive employment agreement between the Grantee and the Company, dated June
23, 2006 (the "Employment Agreement"), as follows. Unless otherwise defined
herein, the terms defined in the Option Agreement shall have the same defined
meanings in this Notice.

     Date of Award                    June 23, 2006

     Vesting Commencement Date        June 23, 2006

     Exercise Price per Share         0.7644

     Total Number of Shares Subject
     to the Option (the "Shares")     1,300,000 Shares

     Total Exercise Price             $993,720

     Type of Option                   Non-Qualified Stock Option

     Expiration Date:                 June 23, 2016

     Post-Termination Vesting and
     Exercise Period:                 As set forth in Section 5 of the Option
                                      Agreement

Vesting Schedule:

     Subject to the Grantee's Continuous Service and other limitations set forth
in this Notice, the Option Agreement, and the Employment Agreement, the Option
may be exercised, in whole or in part, in accordance with the following
schedule:

          (a) Four hundred thousand (400,000) Shares subject to the Option shall
vest when the Company obtains additional financing in an amount which, as
determined by the Board in its sole discretion, will enable the Company to
sustain its operations through the commercial launch of the Company's next
generation product pursuant to the "Pluto" Hemodialysis System Project Plan as
set forth in the Research, Development and License Agreement, entered into on
November 1, 2005, between the Company, DEKA Products Limited Partnership and
DEKA Research and Development Corp., as such Plan may be revised from time to
time ("Pluto");

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          (b) Four hundred thousand (400,000) Shares subject to the Option shall
vest upon the commercial launch of Pluto;

          (c) Two hundred fifty thousand (250,000) Shares subject to the Option
shall vest when the Fair Market Value of the Company's Common Stock is equal to
or above $3.50 per share for more than 75 of 90 consecutive trading days; and

          (d) Two hundred fifty thousand (250,000) Shares subject to the Option
shall vest when the Fair Market Value of the Company's Common Stock is equal to
or above $6.50 per share for more than 75 of 90 consecutive trading days.

     In addition, the Grantee shall have twelve (12) months from the Termination
Date to exercise any Shares that become vested due to the achievement of any of
the foregoing performance milestones during such twelve (12) month period after
the Termination Date.

     Notwithstanding the foregoing, in the event of the commercial launch of
Pluto absent the attainment of the financing described in clause (a) above, all
of the Shares referenced in clauses (a) and (b) above shall vest on the date of
such commercial launch of Pluto.

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     IN WITNESS WHEREOF, the Company and the Grantee have executed this Notice
and agree that the Option is to be governed by the terms and conditions of this
Notice and the Option Agreement.

                                        Aksys, Ltd.,
                                        a Delaware corporation

                                        By: /s/
                                            ------------------------------------

                                        Title:
                                               ---------------------------------

THE GRANTEE ACKNOWLEDGES AND AGREES THAT NOTHING IN THIS NOTICE OR THE OPTION
AGREEMENT SHALL CONFER UPON THE GRANTEE ANY RIGHT WITH RESPECT TO FUTURE AWARDS
OR CONTINUATION OF THE GRANTEE'S CONTINUOUS SERVICE, NOR SHALL IT INTERFERE IN
ANY WAY WITH THE GRANTEE'S RIGHT OR THE RIGHT OF THE COMPANY OR RELATED ENTITY
TO WHICH THE GRANTEE PROVIDES SERVICES TO TERMINATE THE GRANTEE'S CONTINUOUS
SERVICE, WITH OR WITHOUT CAUSE.

     The Grantee acknowledges receipt of a copy of the Option Agreement, and
represents that he or she is familiar with the terms and provisions thereof, and
hereby accepts the Option subject to all of the terms and provisions hereof and
thereof. The Grantee has reviewed this Notice and the Option Agreement in their
entirety, has had an opportunity to obtain the advice of counsel prior to
executing this Notice, and fully understands all provisions of this Notice and
the Option Agreement. The Grantee hereby agrees that all questions of
interpretation and administration relating to this Notice and the Option
Agreement shall be resolved by the Board in accordance with Section 13 of the
Option Agreement. The Grantee further agrees to the venue selection and waiver
of a jury trial in accordance with Section 14 of the Option Agreement. The
Grantee further agrees to notify the Company upon any change in the residence
address indicated in this Notice.

Dated:           06/23/06                Signed:             /s/
       ------------------------------           --------------------------------
                                                             Grantee

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                                   AKSYS, LTD.

                          STOCK OPTION AWARD AGREEMENT

     1. Grant of Option. Aksys, Ltd., a Delaware corporation (the "Company"),
hereby grants to the Grantee (the "Grantee") named in the Notice of Stock Option
Award (the "Notice"), an option (the "Option") to purchase the Total Number of
Shares of Common Stock subject to the Option (the "Shares") set forth in the
Notice, at the Exercise Price per Share set forth in the Notice (the "Exercise
Price") subject to the terms and provisions of this Stock Option Award Agreement
(the "Option Agreement"), the Notice and the executive employment agreement
between the Grantee and the Company, dated June 23, 2006 (the "Employment
Agreement"), which are incorporated herein by reference.

     2. Exercise of Option.

          (a) Right to Exercise. The Option shall be exercisable during its term
in accordance with the Vesting Schedule set out in the Notice and with the
applicable provisions of this Option Agreement.

          (b) Method of Exercise. The Option shall be exercisable by delivery of
an exercise notice (a form of which is attached as Exhibit A) or by such other
procedure as specified from time to time by the Board which shall state the
election to exercise the Option, the whole number of Shares in respect of which
the Option is being exercised, and such other provisions as may be required by
the Board. The exercise notice shall be delivered in person, by certified mail,
or by such other method (including electronic transmission) as determined from
time to time by the Board to the Company accompanied by payment of the Exercise
Price. The Option shall be deemed to be exercised upon receipt by the Company of
such notice accompanied by the Exercise Price, which, to the extent selected,
shall be deemed to be satisfied by use of the broker-dealer sale and remittance
procedure or the net exercise procedure to pay the Exercise Price provided in
Sections 3(d) and 3(e) below.

          (c) Taxes. No Shares will be delivered to the Grantee or other person
pursuant to the exercise of the Option until the Grantee or other person has
made arrangements acceptable to the Board for the satisfaction of applicable
income tax and employment tax withholding obligations, including, without
limitation, obligations incident to the receipt of Shares. Upon exercise of the
Option, the Company or the Grantee's employer may offset or withhold (from any
amount owed by the Company or the Grantee's employer to the Grantee) or collect
from the Grantee or other person an amount sufficient to satisfy such tax
withholding obligations.

     3. Method of Payment. Payment of the Exercise Price shall be made by any of
the following, or a combination thereof, at the election of the Grantee;
provided, however, that such exercise method does not then violate any
Applicable Law and, provided further, that the portion of the Exercise Price
equal to the par value of the Shares must be paid in cash or other legal
consideration permitted by the Delaware General Corporation Law:

          (a) cash;

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          (b) check;

          (c) surrender of Shares or delivery of a properly executed form of
attestation of ownership of Shares as the Board may require which have a Fair
Market Value on the date of surrender or attestation equal to the aggregate
Exercise Price of the Shares as to which the Option is being exercised,
provided, however, that Shares acquired under any other equity compensation plan
or agreement of the Company must have been held by the Grantee for a period of
more than six (6) months (and not used for another award exercise by attestation
during such period); or

          (d) payment through a broker-dealer sale and remittance procedure
pursuant to which the Grantee (i) shall provide written instructions to a
Company-designated brokerage firm to effect the immediate sale of some or all of
the purchased Shares and remit to the Company sufficient funds to cover the
aggregate exercise price payable for the purchased Shares and (ii) shall provide
written directives to the Company to deliver the certificates for the purchased
Shares directly to such brokerage firm in order to complete the sale
transaction; or

          (e) unless such exercise would constitute a violation of any
Applicable Laws as determined by the Board in its sole discretion, payment
through a "net exercise" such that, without the payment of any funds, the
Grantee may exercise the Option and receive the net number of Shares equal to
(i) the number of Shares as to which the Option is being exercised, multiplied
by (ii) a fraction, the numerator of which is the Fair Market Value per Share
less the Exercise Price per Share, and the denominator of which is such Fair
Market Value per Share (the net number of Shares received shall be rounded down
to the nearest whole number of Shares).

     4. Restrictions on Exercise. The Option may not be exercised if the
issuance of the Shares subject to the Option upon such exercise would constitute
a violation of any Applicable Laws. If the exercise of the Option within the
applicable time periods set forth in Section 5, 6 and 7 of this Option Agreement
is prevented by the provisions of this Section 4, the Option shall remain
exercisable until one (1) month after the date the Grantee is notified by the
Company that the Option is exercisable, but in any event no later than the
Expiration Date set forth in the Notice.

     5. Termination or Change of Continuous Service.

          (a) Subject to Section 17 below, in the event the Grantee's Continuous
Service terminates without Cause or by the Grantee with Good Reason, the Grantee
shall have twelve (12) months from the date of such termination (also the
"Termination Date") to exercise any vested Shares subject to the Option. In
addition, the Grantee shall have twelve (12) months from the Termination Date to
exercise any Shares that become vested due to the achievement of any performance
milestones during such twelve (12) month period after the Termination Date as
set forth in the Vesting Schedule of the Notice.

          (b) Subject to Section 17 below, in the event the Grantee's Continuous
Service terminates for Good Reason following a Change of Control of the Company,
the Grantee shall have twelve (12) months from the Termination Date to exercise
any vested Shares subject to the Option.

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          (c) In the event of termination of the Grantee's Continuous Service
for Cause or by the Grantee without Good Reason, the Grantee shall have thirty
(30) days from the Termination Date to exercise any vested Shares subject to the
Option.

          (d) In no event, however, shall the Option be exercised later than the
Expiration Date set forth in the Notice. In the event of the Grantee's change in
status from Employee, Director or Consultant to any other status of Employee,
Director or Consultant, the Option shall remain in effect and the Option shall
continue to vest in accordance with the Vesting Schedule set forth in the
Notice. Except as provided in Sections 6 and 7 below, to the extent that the
Option was unvested on the Termination Date, or if the Grantee does not exercise
the vested portion of the Option within the Post-Termination Exercise Period,
the Option shall terminate.

     6. Disability of Grantee. In the event the Grantee's Continuous Service
terminates as a result of his or her Disability, the Grantee may, but only
within twelve (12) months commencing on the Termination Date (but in no event
later than the Expiration Date), exercise the portion of the Option that was
vested on the Termination Date. To the extent that the Option was unvested on
the Termination Date, or if the Grantee does not exercise the vested portion of
the Option within the time specified herein, the Option shall terminate.

     7. Death of Grantee. In the event of the termination of the Grantee's
Continuous Service as a result of his or her death, or in the event of the
Grantee's death during the Post-Termination Exercise Period or during the twelve
(12) month period following the Grantee's termination of Continuous Service as a
result of his or her Disability, the person who acquired the right to exercise
the Option pursuant to Section 8 may exercise the portion of the Option that was
vested at the date of termination within twelve (12) months commencing on the
date of death (but in no event later than the Expiration Date). To the extent
that the Option was unvested on the date of death, or if the vested portion of
the Option is not exercised within the time specified herein, the Option shall
terminate.

     8. Transferability of Option. The Option may not be transferred in any
manner other than by will or by the laws of descent and distribution, provided,
however, that the Option may be transferred during the lifetime of the Grantee
to the extent and in the manner determined by the Board. Notwithstanding the
foregoing, the Grantee may designate one or more beneficiaries of the Grantee's
Option in the event of the Grantee's death on a beneficiary designation form
provided by the Board. Following the death of the Grantee, the Option, to the
extent provided in Section 7, may be exercised (a) by the person or persons
designated under the deceased Grantee's beneficiary designation or (b) in the
absence of an effectively designated beneficiary, by the Grantee's legal
representative or by any person empowered to do so under the deceased Grantee's
will or under the then applicable laws of descent and distribution. The terms of
the Option shall be binding upon the executors, administrators, heirs,
successors and transferees of the Grantee.

     9. Term of Option. The Option must be exercised no later than the
Expiration Date set forth in the Notice or such earlier date as otherwise
provided herein. After the Expiration

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Date or such earlier date, the Option shall be of no further force or effect and
may not be exercised.

     10. Tax Consequences. The Grantee may incur tax liability as a result of
the Grantee's purchase or disposition of the Shares. THE GRANTEE SHOULD CONSULT
A TAX ADVISER BEFORE EXERCISING THE OPTION OR DISPOSING OF THE SHARES.

     11. Entire Agreement: Governing Law. The Notice, this Option Agreement, and
the Employment Agreement constitute the entire agreement of the parties with
respect to the subject matter hereof and supersede in their entirety all prior
undertakings and agreements of the Company and the Grantee with respect to the
subject matter hereof, and may not be modified adversely to the Grantee's
interest except by means of a writing signed by the Company and the Grantee.
Nothing in the Notice, this Option Agreement, or the Employment Agreement
(except as expressly provided therein) is intended to confer any rights or
remedies on any persons other than the parties. The Notice, this Option
Agreement, and the Employment Agreement are to be construed in accordance with
and governed by the internal laws of the State of Illinois without giving effect
to any choice of law rule that would cause the application of the laws of any
jurisdiction other than the internal laws of the State of Illinois to the rights
and duties of the parties. Should any provision of the Notice or this Option
Agreement be determined to be illegal or unenforceable, such provision shall be
enforced to the fullest extent allowed by law and the other provisions shall
nevertheless remain effective and shall remain enforceable.

     12. Construction. The captions used in the Notice and this Option Agreement
are inserted for convenience and shall not be deemed a part of the Option for
construction or interpretation. Except when otherwise indicated by the context,
the singular shall include the plural and the plural shall include the singular.
Use of the term "or" is not intended to be exclusive, unless the context clearly
requires otherwise.

     13. Administration and Interpretation. Any question or dispute regarding
the administration or interpretation of the Notice or this Option Agreement
shall be submitted by the Grantee or by the Company to the Board. The resolution
of such question or dispute by the Board shall be final and binding on all
persons.

     14. Venue and Waiver of Jury Trial. The Company, the Grantee, and the
Grantee's assignees pursuant to Section 8 (the "parties") agree that any suit,
action, or proceeding arising out of or relating to the Notice or this Option
Agreement shall be brought in the United States District Court for the Northern
District of Illinois (or should such court lack jurisdiction to hear such
action, suit or proceeding, in a Illinois state court in Cook County) and that
the parties shall submit to the jurisdiction of such court. The parties
irrevocably waive, to the fullest extent permitted by law, any objection the
party may have to the laying of venue for any such suit, action or proceeding
brought in such court. THE PARTIES ALSO EXPRESSLY WAIVE ANY RIGHT THEY HAVE OR
MAY HAVE TO A JURY TRIAL OF ANY SUCH SUIT, ACTION OR PROCEEDING. If any one or
more provisions of this Section 14 shall for any reason be held invalid or
unenforceable, it is the specific intent of the parties that such provisions
shall be modified to the minimum extent necessary to make it or its application
valid and enforceable.

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     15. Notices. Any notice required or permitted hereunder shall be given in
writing and shall be deemed effectively given upon personal delivery, upon
deposit for delivery by an internationally recognized express mail courier
service or upon deposit in the United States mail by certified mail (if the
parties are within the United States), with postage and fees prepaid, addressed
to the other party at its address as shown in these instruments, or to such
other address as such party may designate in writing from time to time to the
other party.

     16. Adjustments Upon Changes in Capitalization. Subject to any required
action by the stockholders of the Company, the number of Shares covered by the
Option, the exercise price of the Option, as well as any other terms that the
Board determines require adjustment shall be proportionately adjusted for (i)
any increase or decrease in the number of issued Shares resulting from a stock
split, reverse stock split, stock dividend, combination or reclassification of
the Shares, or similar transaction affecting the Shares, (ii) any other increase
or decrease in the number of issued Shares effected without receipt of
consideration by the Company, or (iii) as the Board may determine in its
discretion, any other transaction with respect to Common Stock including a
corporate merger, consolidation, acquisition of property or stock, separation
(including a spin-off or other distribution of stock or property),
reorganization, liquidation (whether partial or complete) or any similar
transaction; provided, however that conversion of any convertible securities of
the Company shall not be deemed to have been "effected without receipt of
consideration." Such adjustment shall be made by the Board and its determination
shall be final, binding and conclusive. Except as the Board determines, no
issuance by the Company of shares of stock of any class, or securities
convertible into shares of stock of any class, shall affect, and no adjustment
by reason hereof shall be made with respect to, the number or price of Shares
subject to the Option.

     17. Change of Control. Immediately prior to the specified effective date of
a Change of Control, any unvested Shares subject to the Option shall immediately
vest in full. Effective upon the consummation of a Change of Control, the Option
shall terminate. However, the Option shall not terminate to the extent it is
Assumed in connection with the Change of Control.

     18. Definitions. As used herein, the following definitions shall apply:

          (a) "Affiliate" and "Associate" shall have the respective meanings
ascribed to such terms in Rule 12b-2 promulgated under the Exchange Act.

          (b) "Applicable Laws" means the legal requirements applicable to the
Option, if any, under applicable provisions of federal securities laws, state
corporate and securities laws, the Code, the rules of any applicable stock
exchange or national market system, and the rules of any non-U.S. jurisdiction
applicable to Options granted to residents therein.

          (c) "Assumed" means that pursuant to a Change of Control either (i)
the Option is expressly affirmed by the Company or (ii) the contractual
obligations represented by the Option are expressly assumed (and not simply by
operation of law) by the successor entity or its Parent in connection with the
Change of Control with appropriate adjustments to the number and type of
securities of the successor entity or its Parent subject to the Option and the
exercise or purchase price thereof which at least preserves the compensation
element of the Option

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existing at the time of the Change of Control as determined in accordance with
the instruments evidencing the agreement to assume the Option.

          (d) "Board" means the Board of Directors of the Company and shall
include any committee of the Board or Officer of the Company to which the Board
has delegated its authority under this Agreement.

          (e) "Cause" means (i) the Grantee's conviction or plea of nolo
contendere of a felony or any other crime involving dishonesty, breach of trust,
or physical harm to any person (excluding traffic violations that do not relate
to driving while intoxicated or driving under the influence); (ii) the Grantee
has willfully engaged in conduct that is in bad faith and materially injurious
to the Company, including but not limited to, misappropriation of trade secrets,
fraud or embezzlement; or (iii) any material willful breach by the Grantee of
the Employment Agreement that causes material damage to the Company.

          (f) "Change of Control" means a change in ownership or control of the
Company effected through a merger, consolidation or acquisition by any person or
related group of persons (other than an acquisition by the Company or by a
Company-sponsored employee benefit plan or by a person or persons that directly
or indirectly controls, is controlled by, or is under common control with, the
Company) of beneficial ownership (within the meaning of Rule 13d-3 of the
Exchange Act) of securities possessing more than fifty percent of the total
combined voting power of the outstanding securities of the Company.
Notwithstanding anything else contained herein to the contrary, in no event
shall a Change of Control be deemed to occur by reason of (i) a distribution of
the Company's Common Stock held by Durus Life Sciences Master Fund Ltd ("Durus")
to its investors, partners or members, whether as dividend or otherwise, of all
or any portion of the shares of Common Stock held, directly or indirectly, by
Durus or (ii) a sale of all or any portion of the Company's Common Stock held,
directly or indirectly, by Durus in an underwritten public offering (including,
without limitation, a sale of securities of holdings in an underwritten public
offering), unless following such distribution or sale any person or related
group of persons, other than Durus or its affiliates, possess more than fifty
percent of the total combined voting power of the outstanding securities of the
Company.

          (g) "Code" means the Internal Revenue Code of 1986, as amended.

          (h) "Common Stock" means the common stock of the Company.

          (i) "Company" means Aksys, Ltd., a Delaware corporation.

          (j) "Consultant" means any person (other than an Employee or a
Director, solely with respect to rendering services in such person's capacity as
a Director) who is engaged by the Company or any Related Entity to render
consulting or advisory services to the Company or such Related Entity.

          (k) "Continuous Service" means that the provision of services to the
Company or a Related Entity in any capacity of Employee, Director or Consultant
is not interrupted or terminated. In jurisdictions requiring notice in advance
of an effective termination as an Employee, Director or Consultant, Continuous
Service shall be deemed terminated upon the

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actual cessation of providing services to the Company or a Related Entity
notwithstanding any required notice period that must be fulfilled before a
termination as an Employee, Director or Consultant can be effective under
Applicable Laws. A Grantee's Continuous Service shall be deemed to have
terminated either upon an actual termination of Continuous Service or upon the
entity for which the Grantee provides services ceasing to be a Related Entity.
Continuous Service shall not be considered interrupted in the case of (i) any
approved leave of absence, (ii) transfers among the Company, any Related Entity,
or any successor, in any capacity of Employee, Director or Consultant, or (iii)
any change in status as long as the individual remains in the service of the
Company or a Related Entity in any capacity of Employee, Director or Consultant
(except as otherwise provided in the Award Agreement). An approved leave of
absence shall include sick leave, military leave, or any other authorized
personal leave.

          (l) "Director" means a member of the Board or the board of directors
of any Related Entity.

          (m) "Disability" means as defined under the long-term disability
policy of the Company or the Related Entity to which the Grantee provides
services regardless of whether the Grantee is covered by such policy. If the
Company or the Related Entity to which the Grantee provides service does not
have a long-term disability plan in place, "Disability" means that a Grantee is
unable to carry out the responsibilities and functions of the position held by
the Grantee by reason of any medically determinable physical or mental
impairment for a period of not less than one hundred twenty (120) consecutive
days or more than one hundred eighty (180) days in any twelve-month period. A
Grantee will not be considered to have incurred a Disability unless he or she
furnishes proof of such impairment sufficient to satisfy the Board in its
discretion.

          (n) "Employee" means any person, including an Officer or Director, who
is in the employ of the Company or any Related Entity, subject to the control
and direction of the Company or any Related Entity as to both the work to be
performed and the manner and method of performance. The payment of a director's
fee by the Company or a Related Entity shall not be sufficient to constitute
"employment" by the Company.

          (o) "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

          (p) "Fair Market Value" means, as of any date, the value of Common
Stock determined as follows:

               (i) If the Common Stock is listed on one or more established
stock exchanges or national market systems, including without limitation The
Nasdaq Global Select Market, The Nasdaq Global Market or The Nasdaq Capital
Market of The Nasdaq Stock Market, its Fair Market Value shall be the closing
sales price for such stock (or the closing bid, if no sales were reported) as
quoted on the principal exchange or system on which the Common Stock is listed
(as determined by the Board) on the date of determination (or, if no closing
sales price or closing bid was reported on that date, as applicable, on the last
trading date such closing sales price or closing bid was reported), as reported
in The Wall Street Journal or such other source as the Board deems reliable;

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               (ii) If the Common Stock is regularly quoted on an automated
quotation system (including the OTC Bulletin Board) or by a recognized
securities dealer, its Fair Market Value shall be the closing sales price for
such stock as quoted on such system or by such securities dealer on the date of
determination, but if selling prices are not reported, the Fair Market Value of
a share of Common Stock shall be the mean between the high bid and low asked
prices for the Common Stock on the date of determination (or, if no such prices
were reported on that date, on the last date such prices were reported), as
reported in The Wall Street Journal or such other source as the Board deems
reliable; or

               (iii) In the absence of an established market for the Common
Stock of the type described in (i) and (ii), above, the Fair Market Value
thereof shall be determined by the Board in good faith.

          (q) "Good Reason" means,

               (i) absent a Change of Control, as defined by paragraph 18(f),
having a material diminution in, or adverse alteration to, the Grantee's title,
position, or duties, including no longer serving as the highest ranking
executive officer in the Company, provided that (A) the Grantee provides the
Company with written notice of the event constituting Good Reason within sixty
(60) days of such event and the Grantee provides the Company with a period of
sixty (60) days to cure such event, (B) the appointment by the Company of a
Chief Operating Officer, Chief Administrative Officer or similar officer shall
not constitute a material diminution in, or adverse alteration to, the Grantee's
title, position, or duties, provided that the Grantee continues to serve as the
highest ranking executive officer in the Company following any such appointment
and (C) if such material diminution occurs within the first year of the
Grantee's employment with the Company, any resignation by the Grantee as result
of such material diminution shall only be for Good Reason if (1) the Grantee has
first provided the Company with the written notice and cure opportunity provided
in clause (A) above, and (2) such resignation occurs on or after the first year
of the Grantee's employment with the Company; and

               (ii) upon or following a Change of Control, as defined by
paragraph 18(f) herein, either (A) the Grantee's employment is terminated by the
Company not for Cause within twelve (12) months following a Change of Control,
(B) the Grantee no longer is the Chief Executive Officer of a publicly-traded
company immediately following a Change of Control, (C) the Grantee is not a
member of the Board immediately following a Change of Control, (D) the Grantee
does not directly report to the Board immediately following a Change of Control,
or (E) the Grantee provides written notice to the Company of either of the
following events within sixty (60) days of such event and the Grantee provides
the Company with a period of sixty (60) days to cure such event (which event
remains uncured following such period), provided that each such event is
effected by the Company without the consent of the Grantee and occurs within six
(6) months following a Change of Control: (1) a change in the Grantee's job
title at the Company or (2) a material reduction in the Grantee's base salary.

          (r) "Non-Qualified Stock Option" means an Option not intended to
qualify as an incentive stock option within the meaning of Section 422 of the
Code.

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          (s) "Officer" means a person who is an officer of the Company or a
Related Entity within the meaning of Section 16 of the Exchange Act and the
rules and regulations promulgated thereunder.

          (t) "Parent" means a "parent corporation," whether now or hereafter
existing, as defined in Section 424(e) of the Code.

          (u) "Related Entity" means any Parent (other than Durus or any related
investment fund) or Subsidiary of the Company and any business, corporation,
partnership, limited liability company or other entity in which the Company or a
Parent (other than Durus or any related investment fund) or a Subsidiary of the
Company holds a substantial ownership interest, directly or indirectly.

          (v) "Share" means a share of the Common Stock.

          (w) "Subsidiary" means a "subsidiary corporation," whether now or
hereafter existing, as defined in Section 424(f) of the Code.

                                END OF AGREEMENT

                                        9<Page>

                                                                    Exhibit 10.1

            SECOND AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

      Agreement made this 4th day of March, 2006, by and among (i) Optium
Corporation, a Delaware corporation (the "COMPANY") and (ii) those persons whose
names are set forth under the heading "Investors" on the signature pages hereto.

      WHEREAS, the Company and certain of the Investors entered into an Amended
Registration Rights Agreement dated May 23, 2001 as amended on July 12, 2001,
July 31, 2003 and May 12, 2004 (the "EXISTING REGISTRATION RIGHTS AGREEMENT");

      WHEREAS, certain of the Investors are, on the date hereof, acquiring up to
24,475,897 shares of Series D-1 Senior Convertible Preferred Stock, par value
$0.0001 per share, of the Company (the "SERIES D-1 PREFERRED STOCK" and,
together with the Series A Convertible Preferred Stock, par value $0.0001 per
share of the Company (the "SERIES A PREFERRED STOCK"), Series B Convertible
Preferred Stock, par value $0.0001 per share, of the Company (the "SERIES B
PREFERRED STOCK"), Series C Senior Convertible Preferred Stock, par value
$0.0001 per share, of the Company (the "SERIES C PREFERRED STOCK") and Series D
Senior Convertible Preferred Stock, par value $0.0001 per share of the Company
(the "SERIES D PREFERRED STOCK"), the "PREFERRED STOCK") pursuant to that
certain Stock Exchange Agreement by and between the Company, the Investors and
the other parties thereto dated March 4, 2006 (the "STOCK EXCHANGE AGREEMENT");

      WHEREAS, the Company has agreed to grant to the Investors party to the
Stock Exchange Agreement, as an inducement to such Investors to enter into the
Stock Exchange Agreement, the rights granted to such Investors as set forth in
this Agreement;

      WHEREAS, the Investors party to the Stock Exchange Agreement have agreed
to be bound to, as an inducement to the Company to enter into the Stock Exchange
Agreement, the obligations of such Investors as set forth in this Agreement; and

      WHEREAS, the Company and certain of the Investors are parties to the
Existing Registration Rights Agreement, represent the requisite Investors
necessary to amend and restate the Existing Registration Rights Agreement
pursuant to Section 14(d) of the Existing Registration Rights Agreement and
desire to amend and restate the Existing Registration Rights Agreement in its
entirety as set forth below.

      NOW, THEREFORE, in consideration of the mutual covenants herein contained
and other valuable consideration, the receipt and sufficiency of which are
hereby acknowledged, the parties hereto hereby agree as follows:

      1.    CERTAIN DEFINITIONS. As used in this Agreement, the following terms
shall have the following respective meanings:

<Page>

      "CHARTER" shall mean the Fifth Amended and Restated Certificate of
Incorporation as filed with the Delaware Secretary of State.

      "COMMISSION" shall mean the Securities and Exchange Commission or any
other federal agency at the time administering the Securities Act.

      "CONVERSION SHARES" shall mean shares of Common Stock issued or issuable
upon conversion of the Preferred Shares, and any shares of capital stock
received in respect thereof.

      "EXCHANGE ACT" shall mean the Securities Exchange Act of 1934 or any
similar federal statute, and the rules and regulations of the Commission
thereunder, all as the same shall be in effect at the time.

      "KPLJ SHARES" shall mean up to 2,000,000 shares of Common Stock issued or
issuable to Kalkhoven Pettit Levin and Johnson Ventures, LLC ("KPLJ") by the
Company.

      "PREFERRED SHARES" shall mean the shares of Preferred Stock subject to
this Agreement.

      "PREFERRED STOCK" shall mean, collectively, the Series A Preferred Stock,
the Series B Preferred Stock, the Series C Preferred Stock, the Series D
Preferred Stock and the Series D-1 Preferred Stock.

      "PRINCIPALS" shall mean Guifang Li, Patrick LiKamWa and Paul Yu.

      "REGISTRATION EXPENSES" shall mean the expenses so described in SECTION 8.

      "REGISTRABLE STOCK" shall mean (1) the Conversion Shares, excluding
Conversion Shares which have been (a) registered under the Securities Act
pursuant to an effective registration statement filed thereunder and disposed of
in accordance with the registration statement covering them or (b) publicly sold
pursuant to Rule 144 under the Securities Act, (2) for purposes of SECTIONS 2,
3, 4 and 5 hereof, up to 9,600,000 shares of Common Stock held by the Principals
(the "PRINCIPALS' SHARES"), but excluding shares of Common Stock which have been
(a) registered under the Securities Act pursuant to an effective registration
statement filed thereunder and disposed of in accordance with the registration
statement covering them or (b) publicly sold pursuant to Rule 144 under the
Securities Act, (3) any shares of Common Stock, and any shares of Common Stock
issued or issuable upon the conversion or exercise of any other securities,
acquired by the Investors pursuant to the right of first refusal as set forth in
Section 2 of the Second Amended and Restated Stockholders Agreement dated as of
the date hereof and (4) the KPLJ Shares.

      "SECURITIES ACT" shall mean the Securities Act of 1933 or any similar
federal statute, and the rules and regulations of the Commission thereunder, all
as the same shall be in effect at the time.

      "SECURITIES LAWS" shall mean the Securities Act and all applicable state
securities laws, rules and regulations in effect at the time.

      "SELLING EXPENSES" shall mean the expenses so described in SECTION 8.

                                        2
<Page>

      2.    RESTRICTIVE LEGEND. Each certificate representing Preferred Shares,
Conversion Shares or Registrable Stock shall, except as otherwise provided in
this SECTION 2 or in SECTION 3, be stamped or otherwise imprinted with a legend
substantially in the following form:

      "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES
LAWS. THESE SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO
DISTRIBUTION OR RESALE, AND MAY NOT BE SOLD, MORTGAGED, PLEDGED, HYPOTHECATED OR
OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH
SECURITIES UNDER THE SECURITIES ACT OF 1933 AND APPLICABLE STATE SECURITIES
LAWS, OR THE AVAILABILITY OF AN EXEMPTION FROM THE REGISTRATION PROVISIONS OF
THE SECURITIES ACT OF 1933 AND APPLICABLE STATE SECURITIES LAWS."

A certificate shall not bear such legend if, in the opinion of counsel
reasonably satisfactory to the Company, the securities being sold thereby may be
publicly sold without registration under the Securities Act.

      3.    NOTICE OF PROPOSED TRANSFER. Prior to any proposed transfer of any
Preferred Shares, Conversion Shares or Registrable Stock (other than under the
circumstances described in SECTIONS 4, 5 or 6), the holder thereof shall give
written notice to the Company of its intention to effect such transfer. Each
such notice shall describe the manner of the proposed transfer and, if requested
by the Company, shall be accompanied by an opinion of counsel reasonably
satisfactory to the Company to the effect that the proposed transfer may be
effected without registration under the Securities Act, whereupon the holder of
such stock shall be entitled to transfer such stock in accordance with the terms
of its notice; PROVIDED, HOWEVER, that no such opinion of counsel shall be
required for a transfer to one or more partners of the transferor (in the case
of a transferor that is a partnership), to one or more members of the transferor
(in the case of a transferor that is a limited liability company) or to an
affiliated corporation (in the case of a transferor that is a corporation);
PROVIDED, FURTHER, HOWEVER, that any transferee other than a partner or
affiliate of the transferor shall execute and deliver to the Company a
representation letter in form reasonably satisfactory to the Company's counsel
to the effect that the transferee is acquiring Registrable Stock for its own
account, for investment purposes and without any view to distribution thereof.
Each certificate for Preferred Shares or Conversion Shares transferred as above
provided shall bear the legend set forth in SECTION 2, except that such
certificate shall not bear such legend if (i) such legend may be removed in
accordance with the provisions of Rule 144 (or any other rule permitting public
sale without registration under the Securities Act) or (ii) the opinion of
counsel referred to above is to the further effect that the transferee and any
subsequent transferee (other than an affiliate of the Company) would be entitled
to transfer such securities in a public sale without registration under the
Securities Laws. The restrictions provided for in this SECTION 3 shall not apply
to securities which are not required to bear the legend prescribed by SECTION 2
in accordance with the provisions of that Section.

      4.    REQUIRED REGISTRATION.

      (a)      On or after the earlier of (i) May 23, 2006 or (ii) 180 days
after such time as the Company becomes subject to the reporting requirements
under the Exchange Act, either (x) the holders of shares of Registrable Stock
(excluding the Principals' Shares) constituting at least

                                        3
<Page>

a majority in interest of the total shares of Registrable Stock issued or
issuable upon conversion of the issued shares of Series A Preferred Stock or (y)
the holders of shares of Registrable Stock (excluding the Principals' Shares)
constituting at least thirty-five percent (35%) of the total shares of
Registrable Stock issued or issuable upon conversion of the issued shares of
Series B Preferred Stock may request the Company to register under the
Securities Act all or any portion of the shares of Registrable Stock held by
such requesting holder or holders for sale in the manner specified in such
notice (subject to the limitations set forth in subsection 4(d) hereof),
PROVIDED, that the aggregate price to the public of such offering would exceed
$5,000,000. For purposes of this SECTION 4 and SECTIONS 5, 6, 13(a) and 13(d),
the term "Registrable Stock" shall be deemed to include the number of shares of
Registrable Stock which would be issuable to a holder of Preferred Shares upon
conversion of all shares of Preferred Stock held by such holder at such time;
PROVIDED, HOWEVER, that the only securities which the Company shall be required
to register pursuant hereto shall be shares of Common Stock; PROVIDED, FURTHER,
HOWEVER, that, in any underwritten public offering contemplated by this SECTION
4 or SECTIONS 5 and 6, the holders of Preferred Shares shall be entitled to sell
such Preferred Shares to the underwriters for conversion and sale of the shares
of Common Stock issued upon conversion thereof. Notwithstanding anything to the
contrary contained herein, no request may be made under this SECTION 4 within
180 days after the effective date of a registration statement filed by the
Company covering a firm commitment underwritten public offering in which the
holders of Registrable Stock shall have been entitled to join pursuant to
SECTIONS 5 or 6.

      (b)      Following receipt of any notice under this SECTION 4, the Company
shall immediately notify all holders of Registrable Stock (including the
Principals) and Preferred Shares from whom notice has not been received and such
holders shall then be entitled within thirty (30) days thereafter to request the
Company to include in the requested registration all or any portion of their
shares of Registrable Stock. The Company shall use its best efforts to register
under the Securities Act, for public sale in accordance with the method of
disposition described in paragraph (a) above, the number of shares of
Registrable Stock specified in such notice (and in all notices received by the
Company from other holders within thirty (30) days after the giving of such
notice by the Company). The Company shall be obligated to register Registrable
Stock pursuant to SECTION 4(a)(x) on two occasions only and pursuant to SECTION
4(a)(y) on two occasions only; PROVIDED, HOWEVER, that such obligation shall be
deemed satisfied only when a registration statement covering at least eighty
five percent (85%) of the offered shares of Registrable Stock specified in
notices received as aforesaid for sale in accordance with the method of
disposition specified by the requesting holders, shall have become effective or
if such registration statement has been withdrawn prior to the consummation of
the offering at the request of the Investors (other than as a result of a
material adverse change in the business or financial condition of the Company)
and, if such method of disposition is a firm commitment underwritten public
offering, all such shares shall have been sold pursuant thereto.

      (c)      The Company (or at the option of the Company, the holders of
Common Stock) shall be entitled to include in any registration statement
referred to in this SECTION 4, for sale in accordance with the method of
disposition specified by the requesting holders, shares of Common Stock to be
sold by the Company for its own account or such other holders, except as and to
the extent that, in the opinion of the managing underwriter (if such method of
disposition shall be an underwritten public offering), such inclusion would
adversely affect the marketing of the Registrable Stock to be sold subject to
the limitations set forth in SUBSECTION 4(d) hereof).

                                        4
<Page>

Except for registration statements on Form S-4, S-8 or any successor thereto,
the Company will not file with the Commission any other registration statement
with respect to its Common Stock, whether for its own account or that of other
stockholders, from the date of receipt of a notice from requesting holders
pursuant to this SECTION 4 until the completion of the period of distribution of
the registration contemplated thereby.

      (d)      If in the opinion of the managing underwriter the inclusion of
all of the Registrable Stock requested to be registered under this Section would
adversely affect the marketing of such shares, (i) the shares to be sold by the
Company or other holders of Common Stock (including any Registrable Stock held
by the Principals) shall first be excluded, and (ii) the shares of Registrable
Stock to be sold shall be excluded or reduced, as applicable, in such manner
that the shares to be sold shall be allocated among the selling holders pro rata
based on their ownership of Registrable Stock.

      5.    INCIDENTAL REGISTRATION. If the Company at any time (other than
pursuant to SECTION 4 or SECTION 6) proposes to register any of its securities
under the Securities Act for sale to the public, whether for its own account or
for the account of other security holders or both (except with respect to
registration statements on Forms S-4, S-8 or another form not available for
registering the Registrable Stock for sale to the public), each such time it
will give written notice to all holders of outstanding Registrable Stock of its
intention so to do. Upon the written request of any such holder received by the
Company within thirty (30) days after the giving of any such notice by the
Company to register any of its Registrable Stock, the Company will use its best
efforts to cause the Registrable Stock as to which registration shall have been
so requested to be included in the securities to be covered by the registration
statement proposed to be filed by the Company, all to the extent requisite to
permit the sale or other disposition by the holder (in accordance with such
written request) of such Registrable Stock so registered. In the event that any
registration pursuant to this SECTION 5 shall be, in whole or in part, an
underwritten public offering of Common Stock, the number of shares of
Registrable Stock to be included in such an underwriting may be reduced (first
reducing the shares held by the Principals pro rata among the requesting
Principals based upon the number of shares of Registrable Stock held by such
requesting Principals, and then pro rata among the remaining requesting holders
based upon the number of shares of Registrable Stock held by such requesting
holders) if and to the extent that the managing underwriter shall be of the
opinion that such inclusion would adversely affect the marketing of the
securities to be sold by the Company therein; PROVIDED, HOWEVER, that such
number of shares of Registrable Stock shall not be reduced if any shares are to
be included in such underwriting for the account of any person other than the
Company or requesting Investors holding Registrable Stock. Notwithstanding the
foregoing provisions, the Company may withdraw any registration statement
referred to in this SECTION 5 without thereby incurring any liability to the
holders of Registrable Stock.

      6.    REGISTRATION ON FORM S-3; SUSPENSION.

      (a)      Subject to a limit in any twelve (12) month period of (w) two
requested registrations under this Agreement by the holders of shares of
Registrable Stock issued or issuable upon the conversion of the Series A
Preferred Stock, (x) one registration by holders of shares of Registrable Stock
issued or issuable upon the conversion of the Series B Preferred Stock and (y)
one registration by holders of shares of Registrable Stock issued or issuable
upon

                                        5
<Page>

the conversion of the Series D Preferred Stock and (z) one registration by
holders of shares of Registrable Stock issued or issuable upon the conversion of
the Series D-1 Preferred Stock, if at any time (i) a holder or holders of
Registrable Stock then outstanding request that the Company file a registration
statement on Form S-3 or any successor thereto for a public offering of all or
any portion of the shares of Registrable Stock held by such requesting holder or
holders, the reasonably anticipated aggregate price to the public of which would
exceed $1,000,000, (ii) such holder or holders represent at least thirty-five
percent (35%) of the shares of Registrable Stock issued or issuable upon
conversion of the Series B Preferred Stock in the case of a requested
registration by holders of Registrable Stock that is subject to SECTION 6(a)(y)
above have consented to such registration, (iii) such holder or holders
represent at least thirty percent (30%) of the shares of Registrable Stock
issued or issuable upon conversion of the Series D Preferred Stock in the case
of a requested registration by holders of Registrable Stock that is subject to
SECTION 6(a)(y) above have consented to such registration (iv) such holder or
holders represent at least a majority of the Shares of Registrable Stock issued
or issuable upon conversion of the Series D-1 Preferred Stock in the case of a
requested registration by holders of Registrable Stock that is subject to
SECTION 6(a)(z) above have consented to such registration and (v) the Company is
a registrant entitled to use Form S-3 or any successor thereto to register such
shares, then the Company shall use its best efforts to register under the
Securities Act on Form S-3 or any successor thereto, for public sale in
accordance with the method of disposition specified in such notice, the number
of shares of Registrable Stock specified in such notice. Whenever the Company is
required by this SECTION 6 to use its best efforts to effect the registration of
Registrable Stock, each of the procedures and requirements of SECTION 4
(including but not limited to the requirement that the Company notify all
holders of Registrable Stock from whom notice has not been received and provide
them with the opportunity to participate in the offering) shall apply to such
registration, PROVIDED, HOWEVER, that there shall be a limit of four
registrations on Form S-3 which may be requested and obtained under SECTION
6(a)(x).

      (b)      Notwithstanding anything to the contrary set forth in this
Agreement, the Company's obligation under this Agreement to register Registrable
Stock under the Securities Act on registration statements ("REGISTRATION
STATEMENTS") may, upon the reasonable determination of the Board of Directors
made only once during any twelve (12) month period, be suspended in the event
and during such period as unforeseen circumstances (including without limitation
(i) an underwritten primary offering by the Company (which includes no secondary
offering) if the Company is advised in writing by its underwriters that the
registration of the Registrable Stock would have a material adverse effect on
the Company's offering, or (ii) pending negotiations relating to, or
consummation of, a transaction or the occurrence of an event which would require
additional disclosure of material information by the Company in Registration
Statements or such other filings, as to which the Company has a bona fide
business purpose for preserving confidentiality or which renders the Company
unable to comply with Securities and Exchange Commission (the "SEC")
requirements) exist (such unforeseen circumstances being hereinafter referred to
as a "SUSPENSION EVENT") which would make it impractical or inadvisable for the
Company to file the Registration Statements or such other filings or to cause
such to become effective. Such suspension shall continue only for so long as
such event is continuing but in no event for a period longer than one hundred
eight (180) days at any time prior to the time the Company becomes subject to
the reporting requirements under the Exchange Act and ninety (90) days
thereafter. The Company shall notify the Investors of the existence and nature
of any Suspension Event.

                                        6
<Page>

      7.    REGISTRATION PROCEDURES. If and whenever the Company is required by
the provisions of SECTIONS 4, 5 or 6 to use its best efforts to effect the
registration of any shares of Registrable Stock under the Securities Act, the
Company will, as expeditiously as possible:

      (a)      prepare and file with the Commission a registration statement
(which, in the case of an underwritten public offering pursuant to SECTION 4,
shall be on Form S-1 or S-2 (or any successor form) with respect to such
securities and use its best efforts to cause such registration statement to
become and remain effective for the period of the distribution contemplated
thereby (determined as hereinafter provided);

      (b)      prepare and file with the Commission such amendments and
supplements to such registration statement and the prospectus used in connection
therewith as may be necessary to keep such registration statement effective for
the period specified in PARAGRAPH (a) above and comply with the provisions of
the Securities Act with respect to the disposition of all Registrable Stock
covered by such registration statement in accordance with the sellers' intended
method of disposition set forth in such registration statement for such period;

      (c)      as expeditiously as possible, notify each selling holder,
promptly after it shall receive notice thereof, of the time when such
registration statement has become effective or a supplement to any prospectus
forming a part of such registration statement has been filed;

      (d)      furnish to each seller of Registrable Stock and to each
underwriter such number of copies of the registration statement and each such
amendment and supplement thereto (in each case including all exhibits) and the
prospectus included therein (including each preliminary prospectus) as such
persons reasonably may request in order to facilitate the public sale or other
disposition of the Registrable Stock covered by such registration statement;

      (e)      use its best efforts to register or qualify the Registrable Stock
covered by such registration statement under the securities or "blue sky" laws
of such jurisdictions as the sellers of Registrable Stock or, in the case of an
underwritten public offering, the managing underwriter reasonably shall request;
PROVIDED, HOWEVER, that the Company shall not for any such purpose be required
to qualify generally to transact business as a foreign corporation in any
jurisdiction where it is not so qualified or to consent to general service of
process in any such jurisdiction;

      (f)      use its best efforts to list the Registrable Stock covered by
such registration statement with any securities exchange on which the Common
Stock of the Company is then listed;

      (g)      immediately notify each seller of Registrable Stock and each
underwriter under such registration statement, at any time when a prospectus
relating thereto is required to be delivered under the Securities Act, of the
happening of any event of which the Company has knowledge as a result of which
the prospectus contained in such registration statement, as then in effect,
includes an untrue statement of a material fact or omits to state a material
fact required to be stated therein or necessary to make the statements therein
not misleading in light of the circumstances then existing or does not comply
with any requirements of the Securities Act, and promptly prepare and furnish to
such seller a reasonable number of copies of a prospectus supplemented or
amended so that, as thereafter delivered to the purchasers of such Registrable

                                        7
<Page>

Stock, such prospectus shall not include an untrue statement of a material fact
or omit to state a material fact required to be stated therein or necessary to
make the statements therein not misleading in light of the circumstances then
existing and shall comply with the requirements of the Securities Act;

      (h)      if the offering is underwritten and at the request of any seller
of Registrable Stock, use its best efforts to furnish to such seller on the date
that Registrable Stock is delivered to the underwriters for sale pursuant to
such registration: (i) a copy of an opinion dated such date of counsel
representing the Company for the purposes of such registration, addressed to the
underwriters and to such seller, to such effect as reasonably may be requested
by counsel for the underwriters, and (ii) a letter dated such date from the
independent public accountants retained by the Company, addressed to the
underwriters and to such seller, stating that they are independent public
accountants within the meaning of the Securities Act and that, in the opinion of
such accountants, the financial statements of the Company included in the
registration statement or the prospectus, or any amendment or supplement
thereof, comply as to form in all material respects with the applicable
accounting requirements of the Securities Act, and such letter shall
additionally cover such other financial matters (including information as to the
period ending no more than five business days prior to the date of such letter)
with respect to such registration as such underwriters reasonably may request;

      (i)      make available for inspection by each seller of Registrable
Stock, any underwriter participating in any distribution pursuant to such
registration statement, and any attorney, accountant or other agent retained by
such seller or underwriter, reasonable access to all financial and other
records, pertinent corporate documents and properties of the Company, as such
parties may reasonably request, and cause the Company's officers, directors and
employees to supply all information reasonably requested by any such seller,
underwriter, attorney, accountant or agent in connection with such registration
statement;

      (j)      cooperate with the selling holders of Registrable Stock and the
managing underwriters, if any, to facilitate the timely preparation and delivery
of certificates representing Registrable Stock to be sold, such certificates to
be in such denominations and registered in such names as such holders or the
managing underwriters may request at least two business days prior to any sale
of Registrable Stock;

      (k)      promptly provide a transfer agent and registrar for all such
Registrable Shares not later than the effective date of such registration
statement; and

      (l)      permit any holder of Registrable Stock which holder, in the sole
and exclusive judgment, exercised in good faith, of such holder, might be deemed
to be a controlling person of the Company, to participate in good faith in the
preparation of such registration or comparable statement and to require the
insertion therein of material, furnished to the Company in writing, which in the
reasonable judgment of such holder and its counsel should be included.

      For purposes of SECTION 7(a) and 7(b) and of SECTION 4(c), the period of
distribution of Registrable Stock in a firm commitment underwritten public
offering shall be deemed to extend until each underwriter has completed the
distribution of all securities purchased by it, and the period of distribution
of Registrable Stock in any other registration shall be deemed to extend

                                        8
<Page>

until the earlier of the sale of all Registrable Stock covered thereby and one
hundred eighty (180) days after the effective date thereof.

      In connection with each registration hereunder, the sellers of Registrable
Stock will furnish to the Company in writing such information requested by the
Company with respect to themselves and the proposed distribution by them as
reasonably shall be necessary in order to assure compliance with federal and
applicable state securities laws and to make the registration statement correct,
accurate and complete in all respects with respect to such sellers; PROVIDED,
HOWEVER, that this requirement shall not be deemed to limit any disclosure
obligation arising out of any seller's relationship to the Company if one of
such seller's agents or affiliates is an officer, director or control person of
the Company. In addition, the sellers shall, if requested by the Company,
execute such other agreements, which are reasonably satisfactory to them and
which shall contain such provisions as may be customary and reasonable in order
to accomplish the registration of the Registrable Stock.

      In connection with each registration pursuant to SECTIONS 4, 5 or 6
covering an underwritten public offering, the Company and each seller agree to
enter into a written agreement with the managing underwriter selected in the
manner herein provided in such form and containing such provisions as are
customary in the securities business for such an arrangement between such
underwriter and companies of the Company's size and investment stature. The
Company and each seller further agree that the managing underwriter shall be an
investment banking firm of nationally recognized standing.

      8.    EXPENSES. All expenses incurred by the Company in complying with
SECTIONS 4, 5 and 6, including, without limitation, all registration and filing
fees, printing expenses, fees and disbursements of counsel and independent
public accountants for the Company, fees and expenses (including counsel fees)
incurred in connection with complying with state securities or "blue sky" laws,
fees and expenses of one counsel for the selling holders of Registrable Stock in
connection with the registration of Registrable Stock, fees of the National
Association of Securities Dealers, Inc., transfer taxes, fees of transfer agents
and registrars, costs of any insurance which might be obtained, but excluding
any Selling Expenses, are called "REGISTRATION EXPENSES." All underwriting
discounts and selling commissions applicable to the sale of Registrable Stock
and the fees and expenses of more than one counsel for the selling holders of
Registrable Stock in connection with the registration of Registrable Stock are
called "SELLING EXPENSES."

      The Company will pay all Registration Expenses in connection with each
registration statement under SECTIONS 4, 5 or 6. All Selling Expenses in
connection with each registration statement under SECTIONS 4, 5 or 6 shall be
borne by the participating sellers in proportion to the number of shares sold by
each, or by such participating sellers other than the Company (except to the
extent the Company shall be a seller) as they may agree.

      9.    INDEMNIFICATION.

      (a)      In the event of a registration of any of the Registrable Stock
under the Securities Act pursuant to SECTIONS 4, 5 or 6, the Company will
indemnify and hold harmless each holder of Registrable Stock, its officers and
directors, each underwriter of such Registrable

                                        9
<Page>

Stock thereunder and each other person, if any, who controls such seller or
underwriter within the meaning of the Securities Act, against any losses,
claims, damages or liabilities, joint or several, to which such holder, officer,
director, underwriter or controlling person may become subject under the
Securities Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon (i)
any untrue statement or alleged untrue statement of any material fact contained
in any registration statement under which such Registrable Stock was registered
under the Securities Act pursuant to SECTIONS 4, 5 or 6, any preliminary
prospectus or final prospectus contained therein, or any amendment or supplement
thereof, (ii) any blue sky application or other document executed by the Company
specifically for that purpose or based upon written information furnished by the
Company filed in any state or other jurisdiction in order to qualify any or all
of the Registrable Stock under the securities laws thereof (any such
application, document or information herein called a "BLUE SKY APPLICATION"),
(iii) the omission or alleged omission to state therein a material fact required
to be stated therein or necessary to make the statements therein not misleading,
(iv) any violation by the Company or its agents of any rule or regulation
promulgated under the Securities Act applicable to the Company or its agents and
relating to action or inaction required of the Company in connection with such
registration, or (v) any failure to register or qualify the Registrable Stock in
any state where the Company or its agents has affirmatively undertaken or agreed
in writing that the Company (the undertaking of any underwriter chosen by the
Company being attributed to the Company) will undertake such registration or
qualification on the seller's behalf (provided that in such instance the Company
shall not be so liable if it has undertaken its best efforts to so register or
qualify the Registrable Stock) and will reimburse each such holder, and such
officer and director, each such underwriter and each such controlling person for
any legal or other expenses reasonably incurred by them in connection with
investigating or defending any such loss, claim, damage, liability or action;
PROVIDED, HOWEVER, that the Company will not be liable in any such case if and
to the extent that any such loss, claim, damage or liability arises out of or is
based upon an untrue statement or alleged untrue statement or omission or
alleged omission so made in conformity with information furnished by any such
seller, any such underwriter or any such controlling person in writing
specifically for use in such registration statement or prospectus.

      (b)      In the event of a registration of any of the Registrable Stock
under the Securities Act pursuant to SECTIONS 4, 5 or 6, each seller of such
Registrable Stock thereunder, severally and not jointly, will indemnify and hold
harmless the Company, each person, if any, who controls the Company within the
meaning of the Securities Act, each officer of the Company who signs the
registration statement, each director of the Company, each other holder of
Registrable Stock, each underwriter and each person who controls any underwriter
within the meaning of the Securities Act, against all losses, claims, damages or
liabilities, joint or several, to which the Company or such officer, director,
other seller, underwriter or, controlling person may become subject under the
Securities Act or otherwise, insofar as such losses, claims, damages or
liabilities (or actions in respect thereof) arise out of or are based upon any
untrue statement or alleged untrue statement of any material fact contained in
the registration statement under which such Registrable Stock was registered
under the Securities Act pursuant to SECTIONS 4, 5 or 6, any preliminary
prospectus or final prospectus contained therein, or any amendment or supplement
thereof, or any Blue Sky Application or arise out of or are based upon the
omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements therein not misleading, and
will reimburse the Company and each such

                                       10
<Page>

officer, director, other seller, underwriter and controlling person for any
legal or other expenses reasonably incurred by them in connection with
investigating or defending any such loss, claim, damage, liability or action,
PROVIDED, HOWEVER, that such seller will be liable hereunder in any such case if
and only to the extent that any such loss, claim, damage or liability arises out
of or is based upon an untrue statement or alleged untrue statement or omission
or alleged omission made in reliance upon and in conformity with information
pertaining to such seller, as such, furnished in writing to the Company by such
seller specifically for use in such registration statement or prospectus, and
PROVIDED, FURTHER, HOWEVER, that the liability of each seller hereunder shall be
limited to the proportion of any such loss, claim, damage, liability or expense
which is equal to the proportion that the public offering price of the shares
sold by such seller under such registration statement bears to the total public
offering price of all securities sold thereunder, but not in any event to exceed
the proceeds received by such seller from the sale of Registrable Stock covered
by such registration statement.

      (c)      Promptly after receipt by an indemnified party hereunder of
notice of the commencement of any action, such indemnified party shall, if a
claim in respect thereof is to be made against the indemnifying party hereunder,
notify the indemnifying party in writing thereof, but the omission so to notify
the indemnifying party shall not relieve it from any liability which it may have
to such indemnified party other than under this SECTION 9 and shall only relieve
it from any liability which it may have to such indemnified party under this
SECTION 9 if and to the extent the indemnifying party is prejudiced by such
omission. In case any such action shall be brought against any indemnified party
and it shall notify the indemnifying party of the commencement thereof, the
indemnifying party shall be entitled to participate in and, to the extent it
shall wish, to assume and undertake the defense thereof with counsel
satisfactory to such indemnified party, and, after notice from the indemnifying
party to such indemnified party of its election so to assume and undertake the
defense thereof, the indemnifying party shall not be liable to such indemnified
party under this SECTION 9 for any legal expenses subsequently incurred by such
indemnified party in connection with the defense thereof other than reasonable
costs of investigation and of liaison with counsel so selected; PROVIDED,
HOWEVER, that, if the defendants in any such action include both the indemnified
party and the indemnifying party and the indemnified party shall have reasonably
concluded that the interests of the indemnified party reasonably may be deemed
to conflict with the interests of the indemnifying party, the indemnified party
shall have the right to select a separate counsel and to assume such legal
defenses and otherwise to participate in the defense of such action, with the
expenses and fees of such separate counsel and other expenses related to such
participation to be reimbursed by the indemnifying party as incurred.

      (d)      The indemnities provided in this SECTION 9 shall survive the
transfer of any Registrable Stock by such holder.

      10.   CHANGES IN COMMON STOCK OR PREFERRED STOCK. If, and as often as,
there is any change in the Common Stock or the Preferred Stock by way of a stock
split, stock dividend, combination or reclassification, or through a merger,
consolidation, reorganization or recapitalization, or by any other means,
appropriate adjustment shall be made in the provisions hereof so that the rights
and privileges granted hereby shall continue with respect to the Common Stock or
the Preferred Stock as so changed.

                                       11
<Page>

      11.   LIMITATIONS ON SUBSEQUENT REGISTRATION RIGHTS. The Company shall
not, without the prior written consent of (i) the holders of a majority in
interest of the outstanding shares of the Series A Preferred Stock and (ii) the
holders of at least two thirds of the outstanding shares of the Series B
Preferred Stock, enter into any agreement (other than this Agreement) with any
holder or prospective holder of any securities of the Company which grants such
holder or prospective holder rights to include securities of the Company in any
registration statement, unless (a) such rights to include securities in a
registration initiated by the Company or by the holder of the Preferred Shares
are not more favorable than the rights granted to the Principals' Shares under
SECTIONS 4, 5 and 6 of this Agreement, and (b) no rights are granted to initiate
a registration, other than registration pursuant to a registration statement on
Form S-3 (or its successor) in which holders of the Preferred Shares are
entitled to include Registrable Shares on a pro rata basis with such holders
based on the number of shares of Common Stock (on an as-converted basis) owned
by the holders of the Preferred Shares and such holders.

      12.   RULE 144 REPORTING. With a view to making available the benefits of
certain rules and regulations of the Commission which may at any time permit the
sale of the Registrable Stock to the public without registration, at all times
after ninety (90) days after any registration statement covering a public
offering of securities of the Company under the Securities Act shall have become
effective, the Company agrees to:

      (a)      make and keep public information available, as those terms are
understood and defined in Rule 144 under the Securities Act;

      (b)      use its best efforts to file with the Commission in a timely
manner all reports and other documents required of the Company under the
Securities Act and the Exchange Act; and

      (c)      furnish to each holder of Registrable Stock forthwith upon
request a written statement by the Company as to its compliance with the
reporting requirements of such Rule 144 and of the Securities Act and the
Exchange Act, a copy of the most recent annual or quarterly report of the
Company, and such other reports and documents so filed by the Company as such
holder may reasonably request in availing itself of any rule or regulation of
the Commission allowing such holder to sell any Registrable Stock without
registration.

      13.   REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company
represents and warrants to you as follows:

      (a)      The execution, delivery and performance of this Agreement by the
Company have been duly authorized by all requisite corporate action and will not
violate any provision of law, any order of any court or other agency of
government, the Charter or Bylaws of the Company or any provision of any
indenture, agreement or other instrument to which it or any or its properties or
assets is bound, conflict with, result in a breach of or constitute (with due
notice or lapse of time or both) a default under any such indenture, agreement
or other instrument or result in the creation or imposition of any lien, charge
or encumbrance of any nature whatsoever upon any of the properties or assets of
the Company.

      (b)      This Agreement has been duly executed and delivered by the
Company and

                                       12
<Page>

constitutes the legal, valid and binding obligation of the Company, enforceable
in accordance with its terms, except to the extent the indemnification
provisions herein may be deemed not enforceable.

      14.   LIMITATIONS OF LIABILITY AND OBLIGATIONS OF CERTAIN INVESTORS.

      (a)   DEUTSCHE.

                    (i)     Deutsche Asset Management (Australia) Limited as
responsible entity of the Ericsson-Deutsche Technology Fund ("DEUTSCHE") is
bound by this Agreement only in its capacity as responsible entity of the
Ericsson-Deutsche Technology Fund (the "DEUTSCHE TRUST") and in no other
capacity. A liability arising under or in connection with this Agreement is
limited to, and can be enforced against Deutsche only to, the extent to which it
can be satisfied out of the assets of the Deutsche Trust out of which Deutsche
is actually indemnified for the liability. This limitation of Deutsche's
liability applies despite any other provision of this Agreement and extends to
all liabilities and obligations of Deutsche in any way connected with any
representation, warranty, conduct, omission, agreement or transaction related to
this Agreement.

                    (ii)    No party may sue Deutsche in any capacity other than
as responsible entity of the Deutsche Trust, including seeking the appointment
of a receiver (except in relation to property of the Deutsche Trust), a
liquidator, an administrator, or any similar person to Deutsche or prove in any
liquidation, administration or arrangement of or affecting Deutsche (except in
relation to property of the Deutsche Trust).

                    (iii)   The provisions of this SECTION 14 do not apply to
any obligation or liability of Deutsche to the extent that it is not satisfied
because under the deed governing the Deutsche Trust or by operation of law there
is a reduction in the extent of Deutsche's indemnification out of the assets of
the Deutsche Trust, as a result of Deutsche's fraud, negligence or breach of
trust.

                    (iv)    No attorney, agent, receiver or receiver and manager
appointed in accordance with this Agreement has authority to act on behalf of
Deutsche in a way which exposes Deutsche to any personal liability, and no act
or omission of any such person will be considered fraud, negligence or breach of
trust of Deutsche for the purpose of SECTION 14(a)(iii) above.

                    (v)     Notwithstanding any other provision of this
Agreement, Deutsche:

                            (A)  is a funds management company which is part of
Deutsche Bank AG (the "DEUTSCHE GROUP");

                            (B)  is the responsible entity and manager of a
number of managed funds and trusts and has obligations and duties in relation to
each of those managed funds and trusts that are similar to its obligations and
duties in relation to the Deutsche Trust;

                            (C)  may, and other entities in the Deutsche Group
may, invest funds in companies or other entities that may compete with the
Company or Engana Pty Ltd; and

                                       13
<Page>

                            (D)  cannot foster and promote the business of the
Optium or the Company where such conduct would breach its obligations to, or
adversely impact on, the shareholding of Deutsche or other entities in the
Deutsche Group in any such competing company or entity in which funds managed by
Deutsche have been invested.

                    (vi)    Deutsche warrants that, in respect of the Deutsche
Trust, as at the date of this Agreement:

                            (A)  it is the only responsible entity of the
Deutsche Trust;

                            (B)  no action is proposed to remove it as
responsible entity of the Deutsche Trust;

                            (C)  there is no default under the terms of the
constitution of the Deutsche Trust; and

                            (D)  it has the power to enter into and perform this
Agreement; and

                            (E)  Deutsche as responsible entity, has a right of
indemnity out of the trust assets of the Deutsche Trust for all liabilities
incurred by it under this Agreement in accordance with the terms of the trust.

      (b)   TVP.

                    (i)     TVP No. 3 Fund Nominees Pty Limited as trustee of
the TVP No. 3 Fund ("TVP") enters into this Agreement only in its capacity as
trustee of the TVP No. 3 Fund (the "TVP FUND") and in no other capacity. A
liability arising under or in connection with this Agreement is limited to and
can be enforced against TVP in its capacity as trustee of the TVP No. 3 Fund
only to the extent that it can be satisfied out of the property of the TVP No. 3
Fund out of which TVP is actually indemnified for the liability. This limitation
of TVP's liability applies despite any other provision of this Agreement and
extends to all liabilities and obligations of TVP in any way connected with any
representation, warranty, conduct, omission, agreement or transaction related to
this Agreement.

                    (ii)    The parties hereto other than TVP may not sue TVP in
any capacity other than as trustee of the TVP No. 3 Fund or seek the appointment
of a receiver (except in relation to property of the TVP No. 3 Fund), a
liquidator, an administrator, or any similar person to TVP or prove in any
liquidation, administration or arrangement of or affecting TVP (except in
relation to property of the TVP No. 3 Fund).

                    (iii)   The provisions of this clause 14 do not apply to any
obligation or liability of TVP to the extent that it is not satisfied because
under the trust deed of the TVP No. 3 Fund or by operation of law there is a
reduction in or limitation on the extent of TVP's indemnification out of the
assets of the TVP No. 3 Fund, as a result of TVP's fraud, negligence or breach
of trust.

                    (iv)    TVP warrants that, in respect of the TVP No. 3 Fund,
as at the date

                                       14
<Page>

of this Agreement:

                            (A)  it is the only trustee of the TVP No. 3 Fund;

                            (B)  no action is proposed to remove it as trustee
of the TVP No. 3 Fund;

                            (C)  there is no default under the terms of the
constitution of TVP No. 3 Fund;

                            (D)  it has the power to enter into and perform this
Agreement; and

                            (E)  TVP as trustee, has a right of indemnity out of
the trust assets of the TVP No. 3 Fund for all liabilities incurred by it under
this Agreement in accordance with the terms of the trust.

      (c)   STARFISH.

                    (i)     Despite any other provision of this Agreement,
Starfish Technology Fund 1, LP (an incorporated limited partnership under the
Partnership Act 1958 (Vic)) ("STARFISH") is not liable to pay or satisfy, and no
other party is entitled to enforce against Starfish any loss, cost, expense or
damages suffered or incurred by or amounts owing to the other party which result
from a breach or non performance of an obligation, representation or warranty
(whether express, implied by law or otherwise) of Starfish under or in
connection with this Agreement or any other Ancillary Agreements (as such term
is defined in the Stock Exchange Agreement) (including in relation to any
conduct, omission or transaction in relation to this Agreement or any other
Ancillary Agreements) except to the extent that Starfish is able to realise
assets of Starfish (other than assets by way of amounts owed by a general
partner of Starfish or a general partner of that general partner of Starfish or
rights of Starfish against a general partner of or a general partner of that
general partner) to satisfy any liability for the loss, cost, expense or damages
as well as satisfy all other actual or contingent debts and obligations of
Starfish.

                    (ii)    If, as a result of the operation of clause SECTION
14(c)(i) or otherwise, any other party does not recover all loss, cost, expense
or damages suffered or incurred and amounts owing to the other party as a result
of a breach or non performance of any obligation, representation or warranty of
Starfish under or in connection with this Agreement or any other Ancillary
Agreements (whether express or implied by applicable law or otherwise), the
other party has no recourse to Starfish in respect of the shortfall and may not
seek to recover the shortfall by applying to have Starfish wound up.

                    (iii)   No attorney or agent appointed in accordance with
this Agreement or any other Ancillary Agreements has the authority to act on
behalf of Starfish in a way which exposes Starfish to any liability in excess of
any amount for which Starfish may be liable under Section 14(c)(i) and (ii).

                    (iv)    Each party hereto acknowledges and agrees that each
general partner of

                                       15
<Page>

Starfish, each general partner of a general partner of Starfish, each limited
partner of Starfish, each limited partner of a general partner of Starfish and
each of their respective officers, employees, advisers, associates, Affiliates
(as such term is defined in the Stock Exchange Agreement) and related bodies
corporate:

                            (A)  is not liable under this Agreement or any other
Ancillary Agreements or in respect of any matter arising in connection with this
Agreement or any other Ancillary Agreements to any person except to the extent
that liability cannot be excluded by statute or regulation; and

                            (B)  is not the proper party to any claim or other
legal proceedings under this Agreement or any other Ancillary Agreements or in
respect of any matter arising in connection with this Agreement or any other
Ancillary Agreements.

      15.   MISCELLANEOUS.

      (a)      All covenants and agreements contained in this Agreement by or on
behalf of any of the parties hereto shall bind and inure to the benefit of the
respective successors and assigns of the parties hereto (including without
limitation transferees of any Preferred Shares or Registrable Stock), whether so
expressed or not; PROVIDED, HOWEVER, that registration rights conferred herein
on the holders of Preferred Shares, Common Stock or Registrable Stock shall only
inure to the benefit of a transferee of Preferred Shares, Common Stock or
Registrable Stock if (i) there is transferred to such transferee at least
300,000 shares of such stock (as appropriately adjusted for any stock split,
dividend, subdivision or combination) issued prior to November 22, 2000 or
originally issued pursuant to the Series A Preferred Stock Purchase Agreement or
the Series B Preferred Stock Purchase Agreement or (ii) such transferee is a
Qualified Transferee (as such term is defined in that certain Second Amended and
Restated Stockholders Agreement, dated as of the date hereof, by and among the
Company, and the other parties thereto (the "STOCKHOLDERS AGREEMENT")) and
(iii), that such transferee executes a writing agreeing to be bound by the
provisions of this Agreement and the Stockholders Agreement (to the extent the
same remains in effect).

      (b)      All notices, requests, consents and other communications
hereunder shall be in writing and shall be mailed by certified or registered
mail, return receipt requested, postage prepaid, or telexed, in the case of
non-U.S. residents, addressed as follows:

            if to the Company or any other party hereto, at the address of such
party set forth in the Stockholders Agreement with a copy to the Company's
counsel John J. Egan, Esq., Goodwin Procter LLP, Exchange Place, Boston, MA
02109;

            if to any subsequent holder of Preferred Shares or Registrable
Stock, to it at such address as may have been furnished to the Company in
writing by such holder;

            or, in any case, at such other address or addresses as shall have
been furnished in writing to the Company (in the case of a holder of Preferred
Shares or Registrable Stock) or to the holders of Preferred Shares or
Registrable Stock (in the case of the Company) in accordance with the provisions
of this paragraph.

      (c)      This Agreement shall be governed by, construed and enforced in
accordance

                                       16
<Page>

with the internal laws of the Commonwealth of Massachusetts without giving
effect to any choice or conflict of law provision or rule (whether of the
Commonwealth of Massachusetts or any other jurisdiction) that would cause the
application of laws of any jurisdictions other than those of the Commonwealth of
Massachusetts.

      (d)      This Agreement may not be amended or modified, and no provision
hereof may be waived, without the prior written consent of (i) the holders of a
majority in interest of the outstanding shares of the Series A Preferred Stock,
(ii) the holders of at least two thirds of the outstanding shares of the Series
B Preferred Stock, and (iii) the holders of at least two-thirds of the
outstanding shares of Series C Preferred Stock. Notwithstanding the foregoing,
no amendment approved in accordance herewith shall be effective if and to the
extent that such amendment grants to any one or more Investors any rights more
favorable than any rights granted to all other Investors or otherwise treats any
one or more Investors differently than all other Investors. In the event that
any provision of this Agreement is amended by less than unanimous consent of the
parties to this Agreement, a notice and copy of such amendment will be sent
promptly to the parties subject to this Agreement who did not execute such
amendment. To the extent that an amendment or waiver shall impose additional
liabilities or obligations on an Investor beyond that already imposed on such
Investor hereunder prior to such amendment or waiver, then such amendment or
waiver will not be applied to or be enforceable against such Investor without
the prior written consent of such Investor.

      (e)      This Agreement may be executed in two or more counterparts, each
of which shall be deemed an original, but all of which together shall constitute
one and the same instrument. Any person who, after the date hereof, acquires
Preferred Shares shall become a party to this Agreement as a "INVESTOR" and a
holder of "Registrable Stock" for all purposes hereunder, all upon execution by
such person and the Company of a counterpart of this Agreement.

      (f)      The obligations of the Company to register shares of Registrable
Stock under Sections 4, 5 or 6 shall terminate five years after the completion
of its first underwritten firm commitment public offering pursuant to an
effective registration under the Securities Act covering the offering or sale by
the Company of its Common Stock.

      (g)      If requested in writing by the underwriters for any underwritten
public offering of securities of the Company, each holder of Registrable Stock
who is a party to this Agreement shall agree not to sell publicly any shares of
Registrable Stock or any other shares of Common Stock (other than shares of
Registrable Stock or other shares of Common Stock being registered in such
offering), without the consent of such underwriters, for a period of not more
than (i) one hundred eighty (180) days following the effective date of the
registration statement relating to such an offering that is the Company's
initial underwritten public offering or (ii) ninety (90) days following the
effective date of the registration statement relating to any other such
offering; PROVIDED, HOWEVER, that all persons entitled to registration rights
with respect to shares of Common Stock who are not parties to this Agreement and
all executive officers and directors of the Company shall also have agreed not
to sell publicly their Common Stock under the circumstances and pursuant to the
terms set forth in this SECTION 15(g); and further provided, that any such
lock-up agreement shall provide that if the managing underwriter releases any
shares from the lock-up with respect to such offering prior to the scheduled
expiration date, the

                                       17
<Page>

managing underwriter shall release a PRO RATA portion of the Registrable Stock
from such lock-up.

      (h)      The Company shall not grant to any third party any registration
rights comparable to or more favorable than any of those contained herein, so
long as any of the registration rights under this Agreement remains in effect.

      (i)      If any provision of this Agreement shall be held to be illegal,
invalid or unenforceable, such illegality, invalidity or unenforceability shall
attach only to such provision and shall not in any manner affect or render
illegal, invalid or unenforceable any other provision of this Agreement, and
this Agreement shall be carried out as if any such illegal, invalid or
unenforceable provision were not contained herein.

      (j)      The Existing Registration Rights Agreement is of no further force
and effect with respect to any party thereto and is superseded and replaced in
its entirety by this Agreement. This Section 14(j) shall constitute a written
consent pursuant to Section 14(d) of the Existing Registration Rights Agreement
by the Requisite Holders with respect the foregoing.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                                       18
<Page>

   IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                            COMPANY:

                                            OPTIUM, INC.

                                            By: /s/ Eitan Gertel
                                               ---------------------------------
                                               Name: Eitan Gertel
                                               Title: President

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                    INVESTORS:

                                    TL Ventures V Interfund L.P.

                                    By:  TL Ventures V LLC, its general partner

                                    By: /s/ Michael Burns
                                       -----------------------------------------
                                       Name: Michael Burns
                                       Title: Managing Director

                                    TL Ventures V L.P.

                                    By: TL Ventures V Management L.P., its
                                    general partner

                                    By:  TL Ventures V LLC, its Manager

                                    By: /s/ Michael Burns
                                       -----------------------------------------
                                       Name: Michael Burns
                                       Title: Managing Director

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                    INVESTORS:

                                    Battery Investment Partners VI, L.P.

                                    By: /s/ Morgan M. Jones
                                       -----------------------------------------
                                       Name: Morgan M. Jones
                                       Title: Managing Member

                                    Battery Ventures VI, LLC

                                    By: /s/ Morgan M. Jones
                                       -----------------------------------------
                                       Name: Morgan M. Jones
                                       Title: Managing Member

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                    INVESTORS:

                                    CIV, LLC

                                    By: /s/ Gregory E. Smith
                                       -----------------------------------------
                                       Name: Gregory E. Smith
                                       Title: President

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                    INVESTORS:

                                    Kalkhoven Pettit Levin & Johnson Ventures,
                                    LLC

                                    By: /s/ Russell A. Johnson
                                       -----------------------------------------
                                       Name: Russell A. Johnson
                                       Title: Managing Member

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  TPG Ventures, LLC

                                  By: /s/ Jeffrey D. Ekberg
                                      ------------------------------------------
                                      Name: Jeffrey D. Ekberg
                                      Title: Vice President

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  HOLDERS:

                                  /s/ Paul Yu
                                  ---------------------------------------------
                                  Paul Yu

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  HOLDERS AND INVESTORS:

                                  Paul G. Suchoski, Jr. Irrevocable Trust Dtd
                                  12/10/99

                              By: /s/  Sharon Teresa Suchoski and Eitan Gertel
                                  --------------------------------------------
                                  Name: Sharon Teresa Suchoski and Eitan Gertel
                                  Title: Co-Trustees

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  HOLDERS AND INVESTORS:

                                  /s/ Paul Suchoski, Jr.
                                  ----------------------------------------------
                                  Paul Suchoski, Jr.

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  HOLDERS AND INVESTORS:

                                  Eitan Gertel Irrevocable Trust 2001

                                  By: /s/ Morey H. Goldberg
                                     ------------------------------------------
                                     Name: Morey H. Goldberg
                                     Title: Trustee

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  HOLDERS AND INVESTORS:

                                  ------------------------------------------
                                  Eitan Gertel

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                             INVESTORS:

                             Signed for an on behalf of DEUTSCHE ASSET
                             MANAGEMENT (AUSTRALIA) LIMITED ACN
                             076 098 596 in its capacity as trustee and manager
                             AS RESPONSIBLE ENTITY OF THE
                             ERICSSON-DEUTSCHE TECHNOLOGY FUND
                             by its duly authorized attorneys in the presence of

                             Signature of Attorney: /s/ Matthew Koertge
                                                   --------------------
                             Name of Attorney: Matthew Koertge

                             Signature of Witness: /s/ Fiona Holyoke
                                                   -------------------
                             Name of Witness: Fiona Holyoke

                             Signature of Attorney: /s/ Kate Panlino
                                                   -------------------
                             Name of Attorney: Kate Panlino

                             Signature of Witness: /s/ Fiona Holyoke
                                                   -------------------
                             Name of Witness: Fiona Holyoke

                 Signature Page to Registration Rights Agreement

<Page>

          IN WITNESS WHEREOF, the undersigned have executed this Second Amended
and Restated Registration Rights Agreement as a sealed instrument as of the day
and year first above written.

                                  INVESTORS:

                                  EXECUTED BY INTEL CAPITAL
                                  CORPORATION IN ACCORDANCE WITH ITS
                                  CONSTITUENT DOCUMENTS AND THE
                                  LAWS IN FORCE IN ITS PLACE OF
                                  INCORPORATION.

                                  By: /s/ Varun Kapur
                                     --------------------------------
                                     Title: Authorised Signatory

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  EXECUTED BY RIKEI CORPORATION IN
                                  ACCORDANCE WITH ITS CONSTITUENT
                                  DOCUMENTS AND THE LAWS IN FORCE IN
                                  ITS PLACE OF INCORPORATION.

                                  By: /s/ Katsuei Aoyagi
                                     --------------------------------
                                     Katsuei Aoyagi
                                     Title: President and CEO

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  TVP NO 3 FUND NOMINEES PTY LIMITED AS
                                  TRUSTEE OF THE TVP NO 3 FUND

                                  By: /s/ Mark Richards
                                     ---------------------------------------
                                     Title: Authorised Attorney

                                  By: [illegible]
                                     ---------------------------------------
                                     Witnessed:

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  SIGNED BY STARFISH VENTURES LTD. AS AGENT
                                  AND ATTORNEY FOR STARFISH TECHNOLOGY
                                  FUND 1, LP (AN INCORPORATED LIMITED
                                  PARTNERSHIP UNDER THE PARTNERSHIP
                                  ACT 1958 (VIC))

                                  By: /s/ Michael Panaccio
                                     ---------------------------------------
                                     Title: Director

                                  Michael Panaccio
                                  --------------------------------------
                                  Name of Director (print)

                                  /s/ John William Dyson
                                  ---------------------------------------
                                  John William Dyson
                                  ---------------------------------------
                                  Name of Director (print)

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  Signed for Simon Poole by and on behalf of
                                  his duly authorised attorney Steven Frisken
                                  in the presence of:

                                  /s/ Steven Frisken
                                  -----------------------------------------
                                  Simon Poole

                                  /s/ A.E. Cochineas
                                  -----------------------------------------
                                  Witness

                                  A.E. Cochineas
                                  -----------------------------------------
                                  Name of Witness (print)

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  Signed for and on behalf of Ian Clarke by
                                  his duly authorised attorney Steven Frisken
                                  in the presence of:

                                  /s/ Steven Frisken
                                  -----------------------------------------
                                   Ian Clarke

                                  /s/ A.E. Cochineas
                                  -----------------------------------------
                                  Witness

                                  A.E. Cochineas
                                  -----------------------------------------
                                  Name of Witness (print)

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  Signed for and on behalf of Andrew Bartos
                                  by his duly appointed attorney Steven Frisken
                                  in the presence of:

                                  /s/ Steven Frisken
                                  ------------------------------------------
                                   Andrew Bartos

                                  /s/ A.E. Cochineas
                                  -----------------------------------------
                                  Witness

                                  A.E. Cochineas
                                  -----------------------------------------
                                  Name of Witness (print)

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  Signed for and on behalf of Phillip Wickham
                                  by his duly authorised attorney Steven Frisken
                                  in the presence of:

                                  /s/ Steven Frisken
                                  -----------------------------------------
                                   Phillip Wickham

                                  /s/ A.E. Cochineas
                                  -----------------------------------------
                                  Witness

                                  A.E. Cochineas
                                  -----------------------------------------
                                  Name of Witness (print)

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  Signed for and on behalf of Gina Frisken by
                                  her duly authorised attorney Steven Frisken:

                                  /s/ Steven Frisken
                                  -------------------------------------------
                                   Gina Frisken

                                  /s/
                                  -------------------------------------------
                                  Witness

                                  -----------------------------------
                                  Name of Witness (print)

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  Signed for and on behalf of Andrew Kennedy
                                  by his duly appointed attorney Steven Frisken

                                  /s/ Steven Frisken
                                  ------------------------------------------
                                   Andrew Kennedy

                                  /s/ C.T. Allen
                                  ------------------------------------------
                                  Witness

                                  C.T. Allen
                                  -----------------------------------
                                  Name of Witness (print)

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                  Signed for and on behalf of Ian Ritchie by
                                  his duly authorised attorney Steven Frisken

                                  /s/ Steven Frisken
                                  ------------------------------------------
                                   Ian Ritchie

                                  /s/ C.T. Allen
                                  ------------------------------------------
                                  Witness

                                  C.T. Allen
                                  -----------------------------------
                                  Name of Witness (print)

                 Signature Page to Registration Rights Agreement

<Page>

     IN WITNESS WHEREOF, the undersigned have executed this Second Amended and
Restated Registration Rights Agreement as a sealed instrument as of the day and
year first above written.

                                  INVESTORS:

                                 /s/ Russ Johnson
                                 -----------------------------------------
                                  Russ Johnson

                 Signature Page to Registration Rights Agreement

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00106-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00106-of-00352.parquet"}]]