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                                                                 EXHIBIT 4.3


                 FORM OF CONSULTANT STOCK OPTION AGREEMENT


         THIS AGREEMENT, dated as of March 1, 2000 is made by and between
TELLIUM, INC., a Delaware corporation (hereinafter referred to as "Company"),
and ___________________, who resides at __________________________________
(hereinafter referred to as "Optionee").

         WHEREAS, the Company wishes to afford the Optionee the opportunity
to purchase shares of its $0.001 par value common stock ("Common Stock"); and

         WHEREAS, the Company has determined that it would be to the
advantage and in the best interest of the Company and its stockholders to
grant the Option provided for herein to the Optionee as partial compensation
for services rendered under the Consulting Agreement (the "Consulting
Agreement") made and entered into as of the 1st day of January 2000, by and
between the Company and the Optionee.

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

                                    ARTICLE I

                                   DEFNITIONS

         1.1 DEFINED TERMS. Whenever the following terms are used in this
Agreement, they shall have the meaning specified below unless the context
clearly indicates to the contrary. The masculine pronoun shall include the
feminine and neuter, and the singular the plural, where the context so
indicates.

         "BOARD" shall mean the Board of Directors of the Company.

         "COMPANY" shall mean Tellium, Inc., a Delaware corporation.

         "EXCHANGE ACT" shall mean the Securities Exchange Act of 1934, as
amended.

         "EXERCISE SHARES" shall mean shares of stock purchased upon exercise
of the Option or any portion thereof.

         "OPTION" shall mean the non-qualified option to purchase Common
Stock of the Company granted under this Agreement.

         "QUALIFIED OFFERING" shall mean a firm commitment underwritten
public offering of shares of the Company's Common Stock under the Securities
Act, which results in gross proceeds to the

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Company of not less than $50 million at an offering price per share (as
constituted on the date thereof) of not less than $22.88.

         "SECRETARY" shall mean the Secretary of the Company.

         "SECURITIES ACT" shall mean the Securities Act of 1933, as amended.

                                   ARTICLE II

                                 GRANT OF OPTION

         2.1 GRANT OF OPTION. In partial consideration of the Optionee's
services rendered in connection with the Consulting Agreement and for other
good and valuable consideration, on the date hereof the Company irrevocably
grants to the Optionee the option to purchase any part or all of an aggregate
of 12,500 shares of its Common Stock upon the terms and conditions set forth
in this Agreement.

         2.2 PURCHASE PRICE. The purchase price of the shares of stock
covered by the Option shall be $9.15 per share (the "Exercise Price") without
commission or other charge.

                                   ARTICLE III

                            PERIOD OF EXERCISABILITY

         3.1 COMMENCEMENT OF EXERCISABILITY. The Option shall be immediately
exercisable.

         3.2 EXPIRATION OF OPTION. The Option may not be exercised and shall
be null and void upon the earlier of (i) termination of the Consulting
Agreement by the Company due to breach by Tomlinson & Associates or (ii) the
expiration of three (3) years from the date hereof

                                   ARTICLE IV

                               EXERCISE OF OPTION

         4.1 PERSON ELIGIBLE TO EXERCISE. Only the Optionee may exercise the
Option or any portion thereof. In the case of an individual Optionee, after
the death of the Optionee, any exercisable portion of the Option may, prior
to the time when the Option becomes unexercisable under Section 3.2, be
exercised by his or her personal representative or by any person empowered to
do so under the deceased Optionee's will or under the then applicable laws of
descent and distribution.


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         4.2 PARTIAL EXERCISE. Any portion of the Option or the entire Option
may be exercised in whole or in part at any time prior to the time when the
Option becomes unexercisable under Section 3. 1.

         4.3 MANNER OF EXERCISE. The Option may be exercised solely by
delivery to the Secretary or his office of all of the following prior to the
time when the Option becomes unexercisable under Section 3.2:

                  (a) A written notice stating that the Option, or a portion
thereof, is exercised. The notice shall be signed by the Optionee or other
person then entitled to exercise the Option or such portion; and

                  (b) (i) Full cash payment to the Secretary of the Company
for the shares with respect to which such Option or portion is exercised; or

                      (ii) With the consent of the Board in its sole
discretion, property of any kind which constitutes good and valuable
consideration; or

                      (iii) With the consent of the Board, any combination of
the consideration provided in the foregoing subparagraphs (i) and (ii); and

                  (c) A bona fide written representation and agreement, in a
form satisfactory to the Board, signed by the Optionee or other person then
entitled to exercise such Option or portion, stating that the shares of stock
are being acquired for his, her or its own account, for investment and
without any present intention of distributing or reselling said shares or any
of them except as may be permitted under the Securities Act and then
applicable rules and regulations thereunder, and that the Optionee or other
person then entitled to exercise such Option or portion will indemnify the
Company against and hold it free and harmless from any loss, damage, expense
or liability resulting to the Company if any sale or distribution of the
shares by such person is contrary to the representation and agreement
referred to above. The Company may, in its absolute discretion, take whatever
additional actions it deems appropriate to ensure the observance and
performance of such representation and agreement and to effect compliance
with the Securities Act and any other federal or state securities laws or
regulations. Without limiting the generality of the foregoing, the Company
may require an opinion of counsel acceptable to it to the effect that any
subsequent transfer of shares acquired on an Option exercise does not violate
the Securities Act or any other federal or state securities laws or
regulations, and may issue stop-transfer orders covering such shares. Share
certificates evidencing stock issued on exercise of this Option shall bear an
appropriate legend referring to the provisions of this subsection (c) and the
agreements herein. The written representation and agreement referred to in
the first sentence of this subsection (c) shall, however, not be required if
the shares to be issued pursuant to such exercise have been registered under
the Securities Act and any other federal or state securities laws or
regulations, and such registration is then effective in respect of such
shares; and

                  (d) Full payment to the Company of all amounts which, under
federal, state or local tax law, it is required to withhold upon exercise of the
Option in cash, or with the consent of


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the Board, other good and valuable consideration, equal to the sums required
to be withheld, may be used to make all or part of such payment; and

                  (e) In the event the Option or any portion shall be
exercised pursuant to Section 4.1 by any person or persons other than the
Optionee, appropriate proof of the right of such person or persons to
exercise the Option.

         4.4 CONDITIONS TO ISSUANCE OF STOCK CERTIFICATES. The shares of
stock deliverable upon the exercise of the Option, or any portion thereof,
may be either previously authorized but unissued shares or issued shares
which have then been reacquired by the Company. Such shares shall be fully
paid and nonassessable. The Company shall not be required to issue or deliver
any certificate or certificates for Exercise Shares prior to fulfillment of
all of the following conditions:

                  (a) The admission of such shares to listing on all stock
exchanges on which such class of stock is then listed; and

                  (b) The completion of any registration or other
qualification of such shares under any state or federal law or under rulings
or regulations of the Securities and Exchange Commission or of any other
governmental regulatory body, which the Board shall, in its absolute
discretion, deem necessary or advisable; and

                  (c) The obtaining of any approval or other clearance from
any state or federal governmental agency which the Board shall, in its
absolute discretion, determine to be necessary or advisable; and

                  (d) The receipt by the Company of full payment for such
shares, including payment of all amounts which, under federal, state or local
tax law, the Company (or other employer corporation) is required to withhold
upon exercise of the Option; and

                  (e) The lapse of such reasonable period of time following
the exercise of the Option as the Board may from time to time establish for
reasons of administrative convenience.

         4.5 RIGHTS AS STOCKHOLDER. The holder of the Option shall not be,
nor have any of the rights or privileges of, a stockholder of the Company in
respect of any shares purchasable upon the exercise of any part of the Option
unless and until certificates representing such shares shall have been issued
by the Company to such holder.

                                    ARTICLE V

                                OTHER PROVISIONS

         5.1 OPTION NOT TRANSFERABLE. Subject to Section 5.2 hereof, neither the
Option nor any interest or right therein or part thereof shall be sold, pledged,
assigned, or transferred in any manner other than by will or the laws of descent
and distribution, unless and until such Option has


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been exercised, or the shares underlying such Option have been issued, and
all restrictions applicable to such shares have lapsed. Neither the Option
nor any interest or right therein or part thereof shall be liable for the
debts, contracts or engagements of the Optionee or his, her or its successors
in interest or shall be subject to disposition by transfer, alienation,
anticipation, pledge, encumbrance, assignment or any other means whether such
disposition be voluntary or involuntary or by operation of law by judgment,
levy, attachment, garnishment or any other legal or equitable proceedings
(including bankruptcy), and any attempted disposition thereof shall be null
and void and of no effect, except to the extent that such disposition is
permitted by the preceding sentence.

         5.2 CERTAIN PERMITTED TRANSFERS. The provisions of Section 5.1 shall
not apply to a transfer by the Optionee of all or any portion of the Option
to any of the following:

                  (a) current equityholders of the Optionee; or

                  (b) current employees of the Optionee;

PROVIDED that, prior to any such transfer, the Company shall have received
from the transferee a bona fide written representation and agreement, in a
form satisfactory to the Board, signed by the person then receiving such
Option or portion thereof, stating that the Option or portion thereof is
being acquired for his, her or its own account, for investment and without
any present intention of distributing or reselling said Option or portion
thereof except as may be permitted under the Securities Act and then
applicable rules and regulations thereunder, and that such person will
indemnify the Company against and hold it free and harmless from any loss,
damage, expense or liability resulting to the Company if any sale or
distribution of the Option or portion thereof by such person is contrary to
the representation and agreement referred to above. The Company may, in its
absolute discretion, take whatever additional actions it deems appropriate to
ensure the observance and performance of such representation and agreement
and to effect compliance with the Securities Act and any other federal or
state securities laws or regulations. Without limiting the generality of the
foregoing, the Company may require an opinion of counsel acceptable to it to
the effect that any subsequent transfer of Option (or portion thereof) or any
shares acquired on an Option exercise does not violate the Securities Act or
any other federal or state securities laws or regulations, and may issue
appropriate stop-transfer orders. Any such transferee shall also be required
to sign an option agreement substantially in the form hereof.

         On surrender of this Option for transfer pursuant to this Section
5.2, the Company at its expense shall issue to or on the order of the
Optionee and/or such transferee(s) a new warrant or warrants of like tenor,
in the name of the Optionee or as the Optionee (on payment by the Optionee of
any applicable transfer taxes) may direct, for the number of shares issuable
upon exercise hereof.

         5.3 SHARES TO BE RESERVED. The Company shall at all times during the
term of the Option reserve and keep available such number of shares of stock
as will be sufficient to satisfy the requirements of this Agreement.


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         5.4 NOTICES. Any notice to be given under the terms of this
Agreement to the Company shall be addressed to the Company in care of its
Secretary, and any notice to be given to the Optionee shall be addressed to
it at the address set forth herein. By a notice given pursuant to this
Section 5.4, either party may hereafter designate a different address for
notices to be given to him. Any notice which is required to be given to the
Optionee shall, if the Optionee is then deceased, be given to the Optionee's
personal representative if such representative has previously informed the
Company of his, her or its status and address by written notice under this
Section 5.4. Any notice shall be deemed duly given when enclosed in a
properly sealed envelope or wrapper addressed as aforesaid, deposited (with
postage prepaid) in a post office or branch post office regularly maintained
by the United States Postal Service.

         5.5 TITLES. Titles are provided herein for convenience only and are
not to serve as a basis for interpretation or construction of this Agreement.

         5.6 CONSTRUCTION. This Agreement shall be administered, interpreted
and enforced under the internal laws of the State of Delaware without regard
to conflict of laws principles thereof.

         5.7 RESTRICTIONS ON TRANSFER OF SHARES, RIGHT OF FIRST
REFUSAL; REPURCHASE RIGHT

                  (a) Except for Transfers otherwise permitted by Section
5.7(c) below, the Optionee agrees that he will not transfer, sell, assign,
pledge, hypothecate or otherwise dispose of, or agree to dispose of, (each, a
"Transfer") any Exercise Shares at any time without complying with the right
of first refusal set forth in Section 5.7(b) below.

                  (b) If at any time the Optionee receives a bona fide offer
("Offer") to purchase any or all of his, her or its Exercise Shares from a
third party (the "Offeror") which the Optionee wishes to accept, the Optionee
shall cause the Offer to be reduced to writing and shall notify the Company
in writing of his, her or its wish to accept the Offer. The Optionee's notice
shall contain an irrevocable offer to sell such Exercise Shares to the
Company (in the manner set forth below) at a purchase price equal to the
price contained in, and on the same terms and conditions of, the Offer, and
shall be accompanied by a true copy of the Offer (which shall identify the
Offeror). At any time within 30 days after the date of the receipt by the
Company of the Optionee's notice, the Company shall have the right and option
to purchase all, but not less than all, of the Exercise Shares covered by the
Offer either (i) at the same price and on the same terms and conditions as
the Offer or (ii) if the Offer includes any consideration other than cash,
then, at the sole option of the Company, at the equivalent cash price,
determined in good faith by the Board, by delivering a check or checks in the
appropriate amount to the Optionee against delivery of certificates or
instruments representing the Exercise Shares so purchased, appropriately
endorsed by the Optionee; provided that the price to be paid as described
above shall be paid first by reducing the amount of any indebtedness due from
the Optionee to the Company or any of its Subsidiaries. The Company may also
elect (but shall have no obligation) to cause one or more designees to
purchase Exercise Shares covered by the Offer. If at the end of such 30-day
period the Company has not tendered the purchase price for such Exercise
Shares in the manner set forth above, the Optionee may during the succeeding
30-day period sell not less than all of the Exercise Shares


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covered by the Offer to the Offeror on terms no less favorable to the
Optionee than those contained in the Offer. No sale may be made to any
Offeror unless the Offeror agrees in writing with the Company a be bound by
the provisions of this Section 5.7. Promptly after such sale, the Optionee
shall notify the Company of the consummation thereof and shall furnish such
evidence of the completion and time of completion of such sale and of the
terms thereof as may reasonably be requested by the Company. If, at the end
of 30 days following the expiration of the 30-day period during which the
Company may purchase the Exercise Shares, the Optionee has not completed the
sale of such Exercise Shares as aforesaid, all the restrictions on Transfer
contained in this Agreement in effect at that time shall again be in effect
with respect to such Exercise Shares.

                  (c) The provisions of Sections 5.7(a) and 5.7(b) shall not
apply to the following Transfers of Exercise Shares:

                      (i) a Transfer made by the Optionee to the Company; and

                     (ii) a Transfer made to any of the following "Permitted
Transferees":

                                   (a) upon the death of the Optionee to his
executors, administrators, testamentary trustees, legatees or beneficiaries
(the "Optionee's Estate") or a Transfer to the executors, administrators,
testamentary trustees, legatees or beneficiaries of a person who has become a
holder of Exercise Shares in accordance with the terms of this Agreement;

                                    (b) a Transfer made to a trust or
custodianship the beneficiaries of which include only the Optionee, his or
her spouse and his or her lineal descendants, including adopted children (an
"Optionee's Trust");

                                    (c) a Transfer to the Optionee's spouse
and his or her lineal descendants, including adopted children;

                                    (d) a Transfer to a current stockholder
of the Optionee; or

                                    (e) a Transfer to a current employee of
the Optionee.

                  (d) No Transfer of Exercise Shares, whether or not
permitted by Sections 5.7(a), 5.7(b), or 5.7(c) hereof, shall be made or
recorded on the books of the Company, and any such Transfer shall be void and
of no effect, unless:

                      (i) Such Transfer of the Exercise Shares is made pursuant
to an effective registration statement under the Securities Act, or pursuant to
an exemption therefrom with respect to which the Company may, upon request,
require a satisfactory opinion of counsel for the Optionee (which counsel shall
be acceptable to the Company) to the effect that such Transfer is exempt from
the provisions of Section 5 of the Securities Act and any other provision of any
other federal or state securities laws or regulations; and


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                      (ii) The transferee of the Exercise Shares agrees to be
bound by, and executes a counterpart to, an agreement with the Company with
terms substantially similar to the terms set forth in this Section 5.7.

                  (e) Immediately prior to any Transfer of Exercise Shares to
an Optionee's Trust, the Optionee shall provide the Company with a copy of
the instruments creating the Optionee's Trust with the identity of the
beneficiaries of the Optionee's Trust. The Optionee shall notify the Company
prior to any change in the identity of any beneficiary of the Optionee's
Trust.

                  (f) No Transfer of Exercise Shares in violation of this
Agreement shall be made or recorded on the books of the Company and any such
Transfer shall be void and of no effect.

                  (g) (i) Upon the termination of the Consulting Agreement
due to a breach by Tomlinson & Associates (such event being herein called a
"Repurchase Event") then on or after the date of the Repurchase Event, the
Company and/or its assignee(s) may elect to purchase (a "Call") all or (at
the discretion of the Company and with the consent of Optionee (or his or her
legal representative)) any portion of the Exercise Shares then held by such
Optionee and his or her permitted transferees at the price as specified
below, by delivering written notice the "Repurchase Notice") to such
terminated person and such permitted transferees within 180 days of the
occurrence of any Repurchase Event. The Repurchase Notice will set forth the
number of Exercise Shares to be repurchased and the time and place for the
closing of the transaction. The purchase price shall be the fair market
value, as determined in good faith by the Board of Directors of the Company
as of the date of the applicable Repurchase Event.

                    (ii) The closing of the transactions contemplated by this
Section 5.7 shall take place on the date and at the place designed by the
Company or its assignee(s) in the Repurchase Notice, which date shall not be
more than sixty (60) days after the delivery of such notice. The Company
and/or its assignee(s) will pay for the Exercise Shares to be purchased
pursuant to a Call in cash or cash equivalents (including the cancellation of
any purchase-money indebtedness). The Company and/or its assignee(s) will be
entitled to receive customary representations and warranties from the
Optionee and such permitted transferees regarding the sale of the Exercise
Shares, including but not limited to the representation that the Optionee and
any such permitted transferee has good and marketable title to the Exercise
Shares to be transferred free and clear of all liens, claims and other
encumbrances.

                  (h) The restrictions on Transfer and the repurchase right
set forth in this Section 5.7 shall terminate upon a Qualified Offering by
the Company.

         5.8 LEGEND

         The Option, and any securities issuable upon exercise hereof, shall
bear the following legends:


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         "THE SECURITIES REPRESENTED BY THIS CERTIFICATE MAY NOT BE TRANSFERRED,
         SOLD, ASSIGNED, PLEDGED, HYPOTHECATED OR OTHERWISE DISPOSED OF (A
         "TRANSFER') EXCEPT IN ACCORDANCE WITH THE PROVISIONS OF AN OPTION
         AGREEMENT DATED AS OF __________________, 1999. PURSUANT TO SUCH
         AGREEMENT, THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT
         TO A RIGHT OF FIRST REFUSAL AND A REPURCHASE RIGHT IN FAVOR OF TELLIUM,
         INC. AND ANY TRANSFEREE OF THESE SECURITIES TAKES SUBJECT TO SUCH
         RIGHTS. COPIES OF THE OPTION AGREEMENT ARE ON FILE WITH THE COMPANY.

         THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED
         UNDER THE SECURITIES ACT OF 1933 (THE "ACT") OR STATE SECURITIES LAWS
         AND NO TRANSFER OF THESE SECURITIES MAY BE MADE EXCEPT (A) PURSUANT TO
         AN EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT, OR (B) PURSUANT TO
         AN EXEMPTION THEREFROM WITH RESPECT TO WHICH THE COMPANY MAY, UPON
         REQUEST, REQUIRE A SATISFACTORY OPINION OF COUNSEL FOR THE HOLDER THAT
         SUCH TRANSFER IS EXEMPT FROM THE REQUIREMENTS OF THE ACT OR ANY OTHER
         FEDERAL OR STATE I SECURITIES LAWS OR REGULATIONS."

         5.9 CERTAIN REPRESENTATIONS. As further consideration for
acquisition of the Option pursuant to this Agreement, Optionee hereby
represents, warrants and acknowledges to the Company as follows:

                  (a) The Option is being acquired by the Optionee for its,
his or her account, for investment purposes and not with a view to the sale
or distribution of all or any part of the Option (or the shares underlying
the Option), nor with any present intention to sell or in any way distribute
the same, as those terms are used in the Securities Act, and the rules and
regulations promulgated thereunder;

                  (b) Optionee has sufficient knowledge and experience in
financial matters to be capable of evaluating the merits and risks of
acquiring the Option (and the shares underlying the Option);

                  (c) Optionee has reviewed copies of such documents and
other information as Optionee has deemed necessary in order to make an
informed investment decision with respect to its, his or her acquisition of
the Option;

                  (d) Optionee understands that the Option may not be sold,
transferred or otherwise disposed of without registration under the Securities
Act or the availability of an exemption therefrom, and that in the absence of an
effective registration statement covering the Option or an available exemption
from registration under the Securities Act, the Option must be


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held indefinitely. Further, Optionee understands and has the financial
capability of assuming the economic risk of an investment in the Option for
an indefinite period of time;

                  (e) Optionee has been advised by the Company that Optionee
will not be able to dispose of the Option (or the shares underlying the
Option), or any interest therein, without first complying with the relevant
provisions of the Securities Act and any applicable state securities laws;

                  (f) Optionee understands that the provisions of Rule 144
promulgated under the Securities Act, permitting the routine sales of the
securities of certain issuers subject to the terms and conditions thereof,
are not currently, and may not hereafter be, available with respect to the
Option (or the shares underlying the Option); and

                  (g) Optionee acknowledges that the Company is under no
obligation to register the Option (or the shares underlying the Option) or to
furnish any information or take any other action to assist the undersigned in
complying with the terms and conditions of any exemption which might be
available under the Securities Act or any state securities laws with respect
to sales of the Option (or the shares underlying the Option) in the future.

                                   ARTICLE VI

                                   ADJUSTMENTS

6.1 ADJUSTMENTS. The Exercise Price and the number of shares purchasable
hereunder are subject to adjustment from time to time as follows:

         6.1 MERGER, SALE OF ASSETS, ETC. If at any time while this Option or
any portion hereof is outstanding and unexpired, there shall be (i) a
reorganization (other than a combination, reclassification, exchange or
subdivision of shares otherwise provided for herein), (ii) a merger or
consolidation of the Company with or into another corporation in which the
Company is not the surviving entity or a reverse triangular merger in which
the Company is the surviving entity but the shares of the Company's capital
stock outstanding immediately prior to the merger are converted by virtue of
the merger into other property, whether in the form of securities, cash, or
otherwise, or (iii) a sale or transfer of the Company's properties and assets
as, or substantially as, an entirety to any other person, then, as a part of
such reorganization, merger, consolidation, sale or transfer, lawful
provision shall be made so that the holder of this Option shall thereafter be
entitled to receive upon exercise of this Option, during the period specified
herein and upon payment of the Exercise Price then in effect, the number of
shares of stock or other securities or property of the successor corporation
resulting from such reorganization, merger, consolidation, sale or transfer
that a holder of the shares deliverable upon exercise of this Option would
have been entitled to receive in such reorganization, consolidation, merger,
sale or transfer if this Option had been exercised immediately before such
reorganization, consolidation, merger, sale or transfer, all subject to
further adjustment as provided in this Article VI. The foregoing provisions
of this Section 6.1 shall similarly apply to successive reorganizations,
consolidations, mergers,


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sales and transfers and to the stock or securities of any other corporation
that are at the time receivable upon the exercise of this Option. If the per
share consideration payable to the holder hereof for shares in connection
with any such transaction is in a form other than cash or marketable
securities, then the value of such consideration, shall be determined in good
faith by the Company's Board of Directors. In all events, appropriate
adjustment (as determined in good faith by the Company's Board of Directors)
shall be made in the application of the provisions of this Option with
respect to the rights and interest of the Option after the transaction, to
the end that the provisions of this Option shall be applicable after that
event, as near as reasonably may be, in relation to any shares or other
property deliverable after that event upon exercise of this Option.

         6.2 RECLASSIFICATION, ETC. If the Company, at any time while this
Option or any portion hereof remains outstanding and unexpired, by
reclassification of securities or otherwise, shall change any of the
securities as to which purchase rights under this Option exist into the same
or a different number of securities of any other class or classes, this
Option shall thereafter represent the right to acquire such number and kind
of securities as would have been issuable as the result of such change with
respect to the securities that were subject to the purchase rights under this
Option immediately prior to such reclassification or other change and the
Exercise Price therefor shall be appropriately adjusted, all subject to
further adjustment as provided in this Article VI.

         6.3 SPLIT, SUBDIVISION OR COMBINATION OF SHARES. If the Company at
any time while this Option or any portion hereof remains outstanding and
unexpired, shall split, subdivide or combine the securities as to which
purchase rights under this Option exist, into a different number of
securities of the same class, the Exercise Price for such securities shall be
proportionately decreased and the number of securities into which this Option
may be exercised shall be proportionately increased in the case of a split or
subdivision and the Exercise Price shall be proportionately increased and the
number of securities into which this Option may be exercised shall be
proportionately decreased in the case of a combination.

         6.4 ADJUSTMENTS FOR DIVIDENDS IN STOCK OR OTHER SECURITIES OR
PROPERTY. If at any time while this Option or any portion hereof remains
outstanding and unexpired the holders of the securities as to which purchase
rights under this Option exist at the time shall have received, or, on or
after the record date fixed for the determination of eligible stockholders,
shall have become entitled to receive, without payment therefor, other or
additional stock or other securities or property (other than cash) of the
Company by way of dividend, then and in each case, this Option shall
represent the right to acquire, in addition to the number of shares of the
security receivable upon exercise of this Option, and without payment of any
additional consideration therefor, the amount of such other or additional
stock or other securities or property (other than cash) of the Company that
such holder would hold on the date of such exercise had it been the holder of
record of the security receivable upon exercise of this Option on the date
hereof and had thereafter, during the period from the date hereof to and
including the date of such exercise, retained such shares and/or all other
additional stock available by it as aforesaid during such period, giving
effect to all adjustments called for during such period by the provisions of
this Article VI.


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          6.5 CERTIFICATE AS TO ADJUSTMENTS. The Company shall, upon the
reasonable written request of the Optionee, furnish or cause to be furnished
to the Optionee a certificate setting forth: (i) any adjustments and
readjustments; (ii) the Exercise Price at the time in effect; and (iii) the
number of shares and the amount, if any, of other property that at the time
would be received upon the exercise of the Option.






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         IN WITNESS WHEREOF, this Agreement has been executed and delivered by
the parties hereto.

                                       TELLIUM, INC., a Delaware corporation

                                       By:




By:
           Name:
           Title:

Optionee's Taxpayer
Identification Number:





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