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                                                                     EXHIBIT 4.5

                 CERTIFICATE OF DETERMINATION OF PREFERENCES OF

                SERIES E REDEEMABLE CONVERTIBLE PREFERRED STOCK,

                         PAR VALUE $0.001 PER SHARE, OF

                              CRITICAL PATH, INC.,
                            a California corporation

          Pursuant to Section 401 of the California Corporations Code,

         The undersigned, William E. McGlashan, Jr. and Michael J. Zukerman, do
hereby certify that:

         1.       They are the duly elected and acting Chief Executive Officer
and Chairman of the Board of Directors and Senior Vice President, General
Counsel and Secretary, respectively, of Critical Path, Inc., a California
corporation (the "Corporation").

         2.       Pursuant to authority given in the Corporation's Amended and
Restated Articles of Incorporation, the following recitals and resolutions,
creating a series of [___________] ([__________]) shares of Series E Redeemable
Convertible Preferred Stock were duly adopted by the Corporation's Board of
Directors on [__________].

                                   WITNESSETH

         WHEREAS, the Board of Directors is authorized, within the limitations
and restrictions stated in the Amended and Restated Articles of Incorporation of
the Corporation, to provide by resolution or resolutions for the issuance of
shares of Preferred Stock, par value $0.001 per share, of the Corporation, in
one or more classes or series with such voting powers, full or limited, or no
voting powers, and such designations, preferences and relative, participating,
optional or other special rights, and qualifications, limitations or
restrictions as shall be stated and expressed in the resolution or resolutions
providing for the issuance thereof adopted by the Board of Directors, and as are
not stated and expressed in the Amended and Restated Articles of Incorporation,
or any amendment thereto, including (but without limiting the generality of the
foregoing) such provisions as may be desired concerning voting, redemption,
dividends, dissolution or the distribution of assets and such other subjects or
matters as may be fixed by resolution or resolutions of the Board of Directors
under the California Corporations Code; and

         WHEREAS, it is the desire of the Board of Directors, pursuant to its
authority as aforesaid, to authorize and fix the terms of a series of Preferred
Stock and the number of shares constituting such series:

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         NOW, THEREFORE, BE IT RESOLVED:

         1.       Designation and Number of Shares. There shall be hereby
created and established a series of Preferred Stock designated as "Series E
Redeemable Convertible Preferred Stock" (the "Series E Preferred Stock"). The
authorized number of shares of Series E Preferred Stock shall be [___________]
([__________]). Capitalized terms used herein and not otherwise defined shall
have the meanings set forth in Section 10 below.

         2.       Rank. The Series E Preferred Stock shall with respect to the
payment of the Series E Liquidation Payment in the event of Liquidation or
Change of Control and with respect to dividend and redemption rights rank senior
to (i) all classes of common stock of the Corporation (including, without
limitation, the Common Stock, par value $0.001 per share, of the Corporation
(the "Common Stock")), (ii) all classes of preferred stock of the Corporation
(including, without limitation, the Series C Participating Preferred Stock, par
value $0.001 per share, and the Series D Preferred Stock) and (iii) each other
class or series of Capital Stock of the Corporation hereafter created which does
not expressly rank pari passu with or senior to the Series E Preferred Stock
(clauses (i), (ii) and (iii), together, the "Junior Stock").

         3.       Dividends.

                  (a)      Dividend Rate. The holders of shares of Series E
Preferred Stock shall accrue dividends at an annual rate equal to five and
three-fourths percent (5 3/4%) of the Price Per Share, calculated on the basis
of a 360-day year, consisting of twelve 30-day months, and shall accrue on a
daily basis from the date of issuance thereof, whether or not the Corporation
has earnings or profits, whether or not there are funds legally available for
the payment of dividends and whether or not declared by the Board of Directors.
Such dividends shall not be paid in cash and shall instead be added to the
Series E Accreted Value on a semi-annual basis on December 31st and June 30th of
each year (each such date, a "Series E Accrual Date"). If the Corporation
declares and pays any dividends on the Common Stock, then, in that event, the
holders of shares of Series E Preferred Stock shall be entitled to share in such
dividends on a pro rata basis, as if their shares had been converted into shares
of Common Stock pursuant to Section 7(a) below immediately prior to the record
date for determining the stockholders of the Corporation eligible to receive
such dividends.

                  (b)      Other Dividends. The Corporation shall not declare or
pay any dividends on, or make any other distributions with respect to or redeem,
purchase or otherwise acquire for consideration, any other shares of Capital
Stock unless and until all accrued and unpaid dividends on the Series E
Preferred Stock have been paid in full. Notwithstanding Section 2 or this
Section 3(b), dividends shall accrue on the Series D Preferred Stock as provided
in Section 3 of the Amended and Restated Series D Certificate of Determination.

         4.       Liquidation and Change of Control.

                  (a)      Series E Liquidation Payment. Upon the occurrence of
a Liquidation, the holders of shares of Series E Preferred Stock shall be paid
in cash for each share of Series E Preferred Stock held thereby, out of, but
only to the extent of, the assets of the Corporation legally available for
distribution to its stockholders, an amount equal to greater of (i) the sum of

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(A) the Series E Accreted Value of such share of Series E Preferred Stock on the
date of such Liquidation plus (B) all dividends accrued since the previous
Series E Accrual Date or (ii) the aggregate consideration that would be paid to
the holder of the number of shares of Common Stock into which such share of
Series E Preferred Stock is convertible immediately prior to such Liquidation.
If the assets of the Corporation available for distribution to the holders of
shares of Series E Preferred Stock shall be insufficient to permit payment in
full to such holders of the sums which such holders are entitled to receive in
such case, then all of the assets available for distribution to holders of
shares of Series E Preferred Stock shall be distributed among and paid to such
holders ratably in proportion to the amounts that would be payable to such
holders if such assets were sufficient to permit payment in full.

                  (b)      Change of Control. In the event of a Change of
Control, the holders of shares of Series E Preferred Stock shall be paid for
each share of Series E Preferred Stock held thereby, an amount equal to greater
of (i) the sum of (A) the Series E Accreted Value of such share of Series E
Preferred Stock on the date of such Change of Control plus (B) all dividends
accrued since the previous Series E Accrual Date or (ii) the aggregate
consideration that would be paid to the holder of the number of shares of Common
Stock into which such share of Series E Preferred Stock is convertible
immediately prior to the closing of such Change of Control. Such amount shall be
paid in the form of consideration paid in such Change of Control on the closing
date of such Change of Control.

         5.       Redemption.

                  (a)      Optional Redemption.

                           (i)      Series E Optional Redemption Period. The
Corporation shall not have any right to redeem any shares of the Series E
Preferred Stock on or prior to the third anniversary of the Series E Closing
Date. If on any date after the third anniversary of the Series E Closing Date,
but prior to the Series E Automatic Redemption Date, the average closing price
per share of the Common Stock, as reported on NASDAQ or other nationally
recognized securities exchange on which the shares of Common Stock trade, for
any sixty (60) consecutive trading days after such third anniversary date,
equals or exceeds four hundred percent (400%) of the Series E Accreted Value
(the "Series E Optional Redemption Measurement Window"), the Corporation shall
have the right, at its sole option and election, to redeem (unless otherwise
prevented by law) within thirty (30) days following such Series E Optional
Redemption Measurement Window (the "Series E Optional Redemption Period"), all,
but not less than all, of the outstanding shares of Series E Preferred Stock in
cash, at a price per share (the "Series E Optional Redemption Price") equal to
the sum of the Series E Accreted Value plus all dividends accrued since the
previous Series E Accrual Date.

                           (ii)     Optional Redemption Payment. Written notice
of any election by the Corporation to redeem the shares of Series E Preferred
Stock pursuant to Section 5(a) (with a closing date prior to the expiration of
the Series E Optional Redemption Period selected for such redemption (the
"Series E Optional Redemption Date")), shall be delivered in person, mailed by
certified mail, return receipt requested, mailed by overnight mail or sent by
telecopier not less than ten (10), nor more than thirty (30), days prior to such
Series E Optional Redemption Date to the holders of record of the shares of
Series E Preferred Stock, such notice to be addressed to

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each such holder at its address as shown in the records of the Corporation. The
Series E Optional Redemption Price shall be made with respect to each share of
Series E Preferred Stock by wire transfer of immediately available funds or
check as promptly as practicable and, in any event, within seven (7) days after
receipt by the Corporation of the Series E Preferred Stock certificates to
accounts designated in writing by the holders of such shares of Series E
Preferred Stock (in the case of wire transfer) after surrender of the Series E
Preferred Stock certificates pursuant to the following sentence. Upon notice
from the Corporation, each holder of shares of Series E Preferred Stock so
redeemed shall promptly surrender to the Corporation, at any place where the
Corporation shall maintain a transfer agent for its shares of Series E Preferred
Stock, certificates representing the shares so redeemed, duly endorsed in blank
or accompanied by proper instruments of transfer. Notwithstanding anything to
the contrary set forth in this Certificate of Determination, any holder of
Series E Preferred Stock may convert its shares of Series E Preferred Stock
pursuant to Section 7(a) until the Series E Optional Redemption Price has been
paid in full by the Corporation to such holder.

                           (iii)    Termination of Rights. If shares of Series E
Preferred Stock are redeemed in full on the Series E Optional Redemption Date,
then after the Series E Optional Redemption Date, all rights of any holder of
shares of Series E Preferred Stock shall cease and terminate, and such shares of
Series E Preferred Stock shall no longer be deemed to be outstanding; provided,
however, that, if the Corporation defaults in the payment in full of the Series
E Optional Redemption Price, then, subject to Section 5(b), the Corporation may
not redeem the shares of Series E Preferred Stock until the next Series E
Optional Redemption Measurement Window.

                  (b)      Automatic Redemption.

                           (i)      Automatic Redemption Date and Payment. On
the fourth anniversary of the Series E Closing Date (the "Series E Automatic
Redemption Date"), all of the shares of Series E Preferred Stock shall
automatically, with no further action required to be taken by the Corporation or
the holder thereof, be redeemed (unless otherwise prevented by law) in cash, at
a redemption price per share (the "Series E Redemption Price") equal to the sum
of the Series E Accreted Value plus all dividends accrued since the previous
Series E Accrual Date. Written notice of the Series E Automatic Redemption Date
shall be delivered in person, mailed by certified mail, return receipt
requested, mailed by overnight mail or sent by telecopier not less than thirty
(30), nor more than sixty (60), days prior to the Series E Automatic Redemption
Date to the holders of record of the shares of Series E Preferred Stock, such
notice to be addressed to each such holder at its address as shown in the
records of the Corporation. The Series E Redemption Price shall be made with
respect to each share of Series E Preferred Stock by wire transfer of
immediately available funds or check as promptly as practicable and, in any
event, within seven (7) days after receipt by the Corporation of the Series E
Preferred Stock certificates to accounts designated (in the case of wire
transfer) in writing by the holders of such shares of Series E Preferred Stock
after surrender of the Series E Preferred Stock certificates pursuant to the
following sentence. Upon notice from the Corporation, each holder of such shares
of Series E Preferred Stock so redeemed shall promptly surrender to the
Corporation, at any place where the Corporation shall maintain a transfer agent
for its shares of Series E Preferred Stock, certificates representing the shares
so redeemed, duly endorsed in blank or accompanied by proper instruments of
transfer. Notwithstanding anything to the contrary set forth in this

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Certificate of Determination, any holder of Series E Preferred Stock may convert
its shares of Series E Preferred Stock pursuant to Section 7(a) hereof until the
Series E Redemption Price has been paid in full by the Corporation to any such
holder.

                           (ii)     Termination of Rights. If the shares of
Series E Preferred Stock are redeemed in full on the Series E Automatic
Redemption Date, then after the Series E Automatic Redemption Date, all rights
of any holder of such shares of Series E Preferred Stock shall cease and
terminate, and such shares of Series E Preferred Stock shall no longer be deemed
to be outstanding, whether or not the certificates representing such shares have
been received by the Corporation; provided, however, that, if the Corporation
defaults in the payment in full of the Series E Redemption Price, the rights of
the holders of shares of Series E Preferred Stock shall continue until the
Corporation cures such default.

                           (iii)    Insufficient Funds for Redemption. If the
funds of the Corporation available for redemption of the shares of Series E
Preferred Stock on the Series E Automatic Redemption Date are insufficient to
redeem in full the shares of Series E Preferred Stock, the holders of shares of
Series E Preferred Stock shall share ratably in any funds available by law for
redemption of such shares according to the respective amounts which would be
payable with respect to the number of shares owned by them if the shares to be
so redeemed on such Series E Automatic Redemption Date were redeemed in full.
Any shares of Series E Preferred Stock that the Corporation does not redeem on
the Series E Automatic Redemption Date due to insufficient funds shall continue
to be outstanding until redeemed and dividends on such shares shall continue to
accrue and cumulate until redeemed. The Corporation shall in good faith use all
commercially reasonable efforts as expeditiously as possible to eliminate, or
obtain an exception, waiver or exemption from, any and all restrictions that
prevented the Corporation from paying the Series E Redemption Price and
redeeming all of the shares of Series E Preferred Stock. At any time thereafter
when additional funds of the Corporation are available by law for the redemption
of the shares of Series E Preferred Stock, such funds shall be used as promptly
as practicable to redeem the balance of such shares, or such portion thereof for
which funds are available, on the basis set forth above.

         6.       Voting Rights.

                  (a)      General. In addition to the voting rights to which
the holders of Series E Preferred Stock are entitled under or granted by
California law, the holders of Series E Preferred Stock shall be entitled to
vote, in person or by proxy, at a special or annual meeting of stockholders on
all matters entitled to be voted on by holders of shares of Common Stock voting
together as a single class with the Common Stock (and with other shares entitled
to vote thereon, if any), including, without limitation, the election of all of
the directors of the Corporation other than the director elected solely by the
holders of the shares of Series D Preferred Stock pursuant to Section 6(b) of
the Amended and Restated Series D Certificate of Determination. With respect to
any such vote, each share of Series E Preferred Stock shall entitle the holder
thereof to cast that number of votes as is equal to the number of votes that
such holder would be entitled to cast had such holder converted its shares of
Series E Preferred Stock into shares of Common Stock pursuant to Section 7(a)
below on the record date for determining the stockholders of the Corporation
eligible to vote on any such matters.

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                  (b)      Series E Actions. At any meeting of the holders of
shares of Series E Preferred Stock held for the purpose of voting upon any
resolutions requiring the approval of the holders of shares of Series E
Preferred Stock, voting as a separate class or series, the presence in person or
by proxy of the holders of a majority of the shares of Series E Preferred Stock
then outstanding shall constitute a quorum of the Series E Preferred Stock; the
holders of shares of Series E Preferred Stock shall be entitled to cast one vote
per share of Series E Preferred Stock; and such resolution shall be deemed
approved upon the affirmative vote of the holders of a majority of the
outstanding shares of Series E Preferred Stock present in person or represented
by proxy at such meeting.

                  (c)      Action Without a Meeting. Any action required by the
California Corporations Code to be taken at any annual or special meeting of
holders of Series E Preferred Stock, voting as a separate class or series, may
be taken without a meeting, without prior notice and without a vote, if a
consent or consents in writing, setting forth the action so taken, shall be
signed by the holders of outstanding shares of Series E Preferred Stock having
not less than the minimum number of votes that would be necessary to authorize
or take such action at a meeting of the holders of Series E Preferred Stock
pursuant to Section 6(b) and shall be delivered (by hand or certified or
registered mail, return receipt requested) to the Corporation by delivery to its
registered office in the State of California, its principal place of business,
or any officer or agent of the Corporation having custody of the book in which
proceedings of meetings of the holders of Series E Preferred Stock are recorded.
Every written consent shall bear the date of signature of each holder of Series
E Preferred Stock who signs the consent. Prompt notice of the taking of the
corporate action without a meeting by less than unanimous written consent shall,
to the extent, required by applicable law, be given to those holders of Series E
Preferred Stock who have not consented in writing, and who, if the action had
been taken at a meeting, would have been entitled to notice of the meeting if
the record date for such meeting had been the date that written consents signed
by a sufficient number of holders to take the action were delivered to the
Corporation.

                  (d)      Major Actions. Notwithstanding anything to the
contrary set forth in the Amended and Restated Articles of Incorporation or the
By-laws of the Corporation, the affirmative vote of the holders of the
outstanding shares of Series E Preferred Stock acting in accordance with Section
6(b) or 6(c), voting as a separate class, shall be a prerequisite to:

                           (i)      any amendment to, restatement of or waiver
of the terms of the Series E Preferred Stock, including, without limitation, by
merger, consolidation, business combination or otherwise that is not a Change of
Control;

                           (ii)     the issuance, reservation for issuance or
authorization of any Capital Stock of the Corporation or any right or option to
acquire shares of Capital Stock ranking senior to the shares of Series E
Preferred Stock or any increase or decrease in the authorized number of shares
of Series E Preferred Stock; provided, that the Corporation may issue (w)
options or shares pursuant to the Stock Option Plans, (x) shares of Series E
Preferred Stock (A) upon conversion of those certain convertible promissory
notes, with an aggregate principal amount of ten million dollars ($10,000,000),
issued by the Corporation on November [__], 2003, (B) in exchange for those
certain 5 -3/4% Convertible Subordinated Notes, due April 1, 2005, in the
principal face amount of thirty-two million seven hundred ninety-five thousand
dollars

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($32,795,000), issued by the Corporation pursuant to the Corporation's
Indenture, dated March 31, 2000 and (C) issuable pursuant to agreements entered
into prior to the Series E Closing Date, (y) up to ten million (10,000,000)
shares of Series E Preferred Stock issuable at the Price Per Share (excluding
the shares of Series E Preferred Stock issued or authorized pursuant to clause
(A), (B) or (C) above) and (z) issue of the Series E Purchase Rights and the
Rights Shares;

                           (iii)    the redemption of any Junior Stock other
than the repurchase of unvested stock options or restricted stock from
employees, officers, directors or consultants of the Corporation upon
termination of service or in accordance with the Stock Option Plans;

                           (iv)     prior to the payment in full of the Series E
Liquidation Payment, any distribution or payment of any dividend or other
distribution to any Junior Stock, provided that, no consent of the holders of
Series E Preferred Stock shall be required for the accrual of dividends on the
Series D Preferred Stock as provided in Section 3 of the Amended and Restated
Certificate of Determination of Preferences of Series D Preferred Stock; and

                           (v)      any amendment to this Section 6(d).

         7.       Conversion.

                  (a)      Optional Conversion. Any holder of shares of Series E
Preferred Stock shall have the right, at its option, at any time and from time
to time, to convert, subject to the terms and provisions of this Section 7, any
or all of such holder's shares of Series E Preferred Stock into such number of
fully paid and non-assessable shares of Common Stock as is equal to the product
of (i) the number of shares of Series E Preferred Stock being so converted
multiplied by (ii) the quotient of (x) the Series E Accreted Value divided by
(y) the Series E Conversion Price, subject to adjustment as provided in Section
7(c) below. Such conversion right shall be exercised by the surrender of
certificate(s) representing the shares of Series E Preferred Stock to be
converted to the Corporation at any time during usual business hours at its
principal place of business maintained by it (or such other office or agency of
the Corporation as the Corporation may designate by notice in writing to the
holders of shares of Series E Preferred Stock), accompanied by written notice
that the holder elects to convert such shares of Series E Preferred Stock and
specifying the name or names (with address) in which a certificate or
certificates for shares of Common Stock are to be issued and (if so required by
the Corporation) by a written instrument or instruments of transfer in form
reasonably satisfactory to the Corporation duly executed by the holder or its
duly authorized legal representative and transfer tax stamps or funds therefor,
if required pursuant to Section 7(i) below. All certificates representing shares
of Series E Preferred Stock surrendered for conversion shall be delivered to the
Corporation for cancellation and canceled by it. As promptly as practicable
after the surrender of any shares of Series E Preferred Stock, in any event
within seven (7) days of the receipt of such certificates, the Corporation shall
(subject to compliance with the applicable provisions of federal and state
securities laws) deliver to the holder of such shares so surrendered
certificate(s) representing the number of fully paid and nonassessable shares of
Common Stock into which such shares are entitled to be converted. At the time of
the surrender of such certificate(s), the Person in whose name any
certificate(s) for shares of Common Stock shall be issuable upon such conversion
shall be deemed to be the holder of record of such shares of Common Stock on
such date,

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notwithstanding that the share register of the Corporation shall then be closed
or that the certificates representing such Common Stock shall not then be
actually delivered to such Person.

                  (b)      Termination of Rights. On the date of such optional
conversion pursuant to Section 7(a) above all rights with respect to the shares
of Series E Preferred Stock so converted, including the rights, if any, to
receive notices and vote, shall terminate, except only the rights of holders
thereof to (i) receive certificates for the number of shares of Common Stock
into which such shares of Series E Preferred Stock have been converted and (ii)
exercise the rights to which they are entitled as holders of Common Stock.

                  (c)      (i)      Dividend, Subdivision, Combination or
Reclassification of Common Stock. In the event that the Corporation shall at any
time or from time to time, prior to conversion of shares of Series E Preferred
Stock (w) pay a dividend or make a distribution on the outstanding shares of
Common Stock payable in Capital Stock of the Corporation, (x) subdivide the
outstanding shares of Common Stock into a larger number of shares, (y) combine
the outstanding shares of Common Stock into a smaller number of shares or (z)
issue any shares of its Capital Stock in a reclassification of the Common Stock
(other than any such event for which an adjustment is made pursuant to another
clause of this Section 7(c)), then, and in each such case, the Series E
Conversion Price in effect immediately prior to such event shall be adjusted
(and any other appropriate actions shall be taken by the Corporation) so that
the holder of any share of Series E Preferred Stock thereafter surrendered for
conversion shall be entitled to receive the number of shares of Common Stock or
other securities of the Corporation that such holder would have owned or would
have been entitled to receive upon or by reason of any of the events described
above, had such share of Series E Preferred Stock been converted immediately
prior to the occurrence of such event. An adjustment made pursuant to this
Section 7(c)(i) shall become effective retroactively (x) in the case of any such
dividend or distribution, to a date immediately following the close of business
on the record date for the determination of holders of Common Stock entitled to
receive such dividend or distribution or (y) in the case of any such
subdivision, combination or reclassification, to the close of business on the
day upon which such corporate action becomes effective.

                           (ii)     Certain Distributions. In case the
Corporation shall at any time or from time to time, prior to conversion of
shares of Series E Preferred Stock, distribute to all holders of shares of the
Common Stock (including any such distribution made in connection with a merger
or consolidation in which the Corporation is the resulting or surviving Person
and the Common Stock is not changed or exchanged) cash, evidences of
indebtedness of the Corporation or another issuer, securities of the Corporation
or another issuer or other assets (excluding cash dividends in which holders of
shares of Series E Preferred Stock participate, in the manner provided in
Section 3(b); dividends payable in shares of Common Stock for which adjustment
is made under another paragraph of this Section 7(c); and any distribution in
connection with an Excluded Transaction) or rights or warrants to subscribe for
or purchase of any of the foregoing, then, and in each such case, the Series E
Conversion Price then in effect shall be adjusted (and any other appropriate
actions shall be taken by the Corporation) by multiplying the Series E
Conversion Price in effect immediately prior to the date of such distribution by
a fraction (x) the numerator of which shall be the Current Market Price of the
Common Stock immediately prior to the date of distribution less the then fair
market value (as determined by the Board of Directors in the exercise of their
fiduciary duties) of the portion of the cash, evidences of indebtedness,

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securities or other assets so distributed or of such rights or warrants
applicable to one share of Common Stock and (y) the denominator of which shall
be the Current Market Price of the Common Stock immediately prior to the date of
distribution (but such fraction shall not be greater than one); provided,
however, that no adjustment shall be made with respect to any distribution of
rights or warrants to subscribe for or purchase securities of the Corporation if
the holder of shares of Series E Preferred Stock would otherwise be entitled to
receive such rights or warrants upon conversion at any time of shares of Series
E Preferred Stock into Common Stock. Such adjustment shall be made whenever any
such distribution is made and shall become effective retroactively to a date
immediately following the close of business on the record date for the
determination of stockholders entitled to receive such distribution.

                           (iii)    Other Changes. In case the Corporation at
any time or from time to time, prior to the conversion of shares of Series E
Preferred Stock, shall take any action affecting its Common Stock similar to or
having an effect similar to any of the actions described in Sections 7(c)(i) or
(ii) above or Section 7(f) below (but not including any action described in any
such Section) and the Board of Directors in good faith determines that it would
be equitable in the circumstances to adjust the Series E Conversion Price as a
result of such action, then, and in each such case, the Series E Conversion
Price shall be adjusted in such manner and at such time as the Board of
Directors in good faith determines would be equitable in the circumstances (such
determination to be evidenced in a resolution, a certified copy of which shall
be mailed to the holders of shares of Series E Preferred Stock).

                           (iv)     No Adjustment. Notwithstanding anything
herein to the contrary, no adjustment under this Section 7(c) need be made to
the Series E Conversion Price if the Corporation receives written notice from
holders of a majority of the outstanding shares of Series E Preferred Stock that
no such adjustment is required.

                  (d)      Abandonment. If the Corporation shall take a record
of the holders of its Common Stock for the purpose of entitling them to receive
a dividend or other distribution, and shall thereafter and before the
distribution to stockholders thereof legally abandon its plan to pay or deliver
such dividend or distribution, then no adjustment in the Series E Conversion
Price shall be required by reason of the taking of such record.

                  (e)      Certificate as to Adjustments. Upon any adjustment in
the Series E Conversion Price, the Corporation shall within a reasonable period
(not to exceed ten (10) Business Days) following any of the foregoing
transactions deliver to each registered holder of shares of Series E Preferred
Stock a certificate, signed by (i) the Chief Executive Officer of the
Corporation and (ii) the Chief Financial Officer of the Corporation, setting
forth in reasonable detail the event requiring the adjustment and the method by
which such adjustment was calculated and specifying the increased or decreased
Series E Conversion Price then in effect following such adjustment.

                  (f)      Reorganization, Reclassification. In case of any
merger or consolidation of the Corporation (other than a Change of Control) or
any capital reorganization, reclassification or other change of outstanding
shares of Common Stock (other than a change in par value, or from par value to
no par value, or from no par value to par value) (each, a "Transaction"), the
holder of each share of Series E Preferred Stock shall have the right to receive
in such

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Transaction, in exchange for each share of Series E Preferred Stock, a security
identical to (and not less favorable than) the Series E Preferred Stock, and
provision shall be made therefor in the agreement, if any, relating to such
Transaction.

                  (g)      Reservation of Common Stock. The Corporation shall at
all times reserve and keep available for issuance upon the conversion of shares
of Series E Preferred Stock, such number of its authorized but unissued shares
of Common Stock as will from time to time be sufficient to permit the conversion
of all outstanding shares of Series E Preferred Stock, and shall take all action
to increase the authorized number of shares of Common Stock if at any time there
shall be insufficient authorized but unissued shares of Common Stock to permit
such reservation or to permit the conversion of all outstanding shares of Series
E Preferred Stock; provided, that the holders of shares of Series E Preferred
Stock shall vote such shares in favor of any such action that requires a vote of
stockholders.

                  (h)      No Conversion Tax or Charge. The issuance or delivery
of certificates for Common Stock upon the conversion of shares of Series E
Preferred Stock shall be made without charge to the converting holder of shares
of Series E Preferred Stock for such certificates or for any tax in respect of
the issuance or delivery of such certificates or the securities represented
thereby, and such certificates shall be issued or delivered in the respective
names of, or (subject to compliance with the applicable provisions of federal
and state securities laws) in such names as may be directed by, the holders of
the shares of Series E Preferred Stock converted; provided, however, that the
Corporation shall not be required to pay any tax which may be payable in respect
of any transfer involved in the issuance and delivery of any such certificate in
a name other than that of the holder of the shares of Series E Preferred Stock
converted, and the Corporation shall not be required to issue or deliver such
certificate unless or until the Person or Persons requesting the issuance or
delivery thereof shall have paid to the Corporation the amount of such tax or
shall have established to the reasonable satisfaction of the Corporation that
such tax has been paid.

                  (i)      Limitations on Conversions. Each holder of the Series
E Preferred Stock's right to convert its shares of Series E Preferred Stock into
shares of Common Stock shall not be limited by any notice delivered by the
Corporation of any proposed redemption, Change of Control or any other event
that notwithstanding this subsection (i) shall purport to limit such conversion
right.

         8.       Certain Remedies. Any registered holder of shares of Series E
Preferred Stock shall be entitled to an injunction or injunctions to prevent
breaches of the provisions of this Certificate of Determination and to enforce
specifically the terms and provisions of this Certificate of Determination in
any court of the United States or any state thereof having jurisdiction, this
being in addition to any other remedy to which such holder may be entitled at
law or in equity.

         9.       Business Day. If any payment shall be required by the terms
hereof to be made on a day that is not a Business Day, such payment shall be
made on the immediately succeeding Business Day.

                                       10
<PAGE>

         10.      Definitions. As used in this Certificate of Determination, the
following terms shall have the following meanings (with terms defined in the
singular having comparable meanings when used in the plural and vice versa),
unless the context otherwise requires:

                  "Affiliate" shall mean any Person who is an "affiliate" as
defined in Rule 12b-2 of the General Rules and Regulations under the Exchange
Act.

                  "Amended and Restated Series D Certificate of Determination"
means the Corporation's Certificate of Determination of Preference of Series D
Cumulative Redeemable Convertible Preferred Stock, as amended from time to time.

                  "Board of Directors" means the Board of Directors of the
Corporation.

                  "Business Day" means any day except a Saturday, a Sunday, or
other day on which commercial banks in the State of New York or the State of
California are authorized or required by law or executive order to close.

                  "Capital Stock" means, with respect to any Person, any and all
shares, interests, participations, rights in, or other equivalents (however
designated and whether voting or non-voting) of, such Person's capital stock
(including, without limitation, common stock and preferred stock) and any and
all rights, warrants or options exchangeable for or convertible into such
capital stock.

                  "Certificate of Determination" means this Certificate of
Determination of Preferences of Series E Redeemable Convertible Preferred Stock,
as amended from time to time.

                  "Change of Control" means (i) any merger, consolidation or
other business combination transaction (or series of related transactions) in
which the stockholders owning a majority of the voting securities of the
Corporation prior to such transaction do not own a majority of the voting
securities of the surviving entity, (ii) any tender offer, exchange offer or
other transaction whereby any person or "group" other than the Investors obtains
a majority of the outstanding shares of capital stock entitled to vote in the
election of the Board of Directors, (iii) any proxy contest in which a majority
of the Board of Directors (or persons appointed by such Board of Directors)
prior to such contest do not constitute a majority of the Board of Directors
after such contest or (iv) any other transaction described in any stockholder
rights agreement or "poison pill", if any, to which the Corporation is a party,
which permits the holders of any rights or similar certificates to exercise the
rights evidenced thereby and pursuant to which the Board of Directors does not
waive the application of such stockholder rights agreement or "poison pill."

                  "Commission" means the United States Securities and Exchange
Commission.

                  "Common Stock" shall have the meaning ascribed to it in
Section 2(a) hereof.

                  "Common Stock Equivalent" shall mean any security or
obligation which is by its terms convertible, exchangeable or exercisable into
or for shares of Common Stock, including, without limitation, shares of Series D
Preferred Stock, shares of Series E Preferred Stock and any

                                       11
<PAGE>

option, warrant or other subscription or purchase right with respect to Common
Stock or any Common Stock Equivalent.

                  "Corporation" shall have the meaning ascribed to it in the
first paragraph of this Certificate of Determination.

                  "Current Market Price" per share of Capital Stock of any
Person shall mean, as of the date of determination, (a) the average of the daily
Market Price under clause (a), (b) or (c) of the definition thereof of such
Capital Stock during the immediately preceding thirty (30) trading days ending
on such date, and (b) if such Capital Stock is not then listed or admitted to
trading on any national securities exchange or quoted in the over-the-counter
market, then the Market Price under clause (d) of the definition thereof on such
date.

                  "Exchange Act" means the Securities Exchange Act of 1934, as
amended, and the rules and regulations of the Commission promulgated thereunder.

                  "Excluded Transaction" means (a) any issuance of shares of
stock or options to purchase shares of Series E Preferred Stock or Common Stock
pursuant to the Stock Option Plans, (b) any issuance of Common Stock (i) upon
the conversion of shares of Series E Preferred Stock or shares of Series D
Preferred Stock, (ii) as a dividend on shares of Series E Preferred Stock or
shares of Series D Preferred Stock or (iii) upon conversion or exercise of any
Common Stock Equivalents, (c) any issuance of Common Stock in connection with
any Series E Liquidation Payment or Series D Liquidation Payment, (d) Capital
Stock issued in consideration of an acquisition, approved by the Board of
Directors, of another Person, (e) shares of Common Stock and Common Stock
Equivalents issued in strategic transactions (which may not be private equity or
venture capital financing transactions), approved by the Board of Directors, to
Persons that are not principally engaged in financial investing, (f) up to ten
million (10,000,000) shares of Series E Preferred Stock issuable at the Price
Per Share, (g) the issuance of the Series E Purchase Rights and the Rights
Shares and (h) shares of Series E Preferred Stock issuable pursuant to
agreements entered into prior to the Series E Closing Date.

                  "GAAP" means United States generally accepted accounting
principles in effect from time to time.

                  "Investors" means General Atlantic Partners 74, L.P., GAP
Coinvestment Partners II, L.P., GapStar, LLC, GAP-W, LLC, GAPCO GmbH & Co. KG,
Campina Enterprises Limited, Cenwell Limited, Great Affluent Limited,
Dragonfield Limited and Lion Cosmos Limited and the Affiliates of the foregoing,
provided that Affiliates shall be deemed not to include any portfolio companies
of any of the foregoing.

                  "Junior Stock" shall have the meaning ascribed to it in
Section 2(a) hereof.

                  "Liquidation" shall mean the voluntary or involuntary
liquidation under applicable bankruptcy or reorganization legislation, or the
dissolution or winding up of the Corporation.

                                       12
<PAGE>

                  "Market Price" shall mean, with respect to the Capital Stock
of any Person, as of the date of determination, (a) if such Capital Stock is
listed on a national securities exchange, the closing price per share of such
Capital Stock on such date published in The Wall Street Journal (National
Edition) or, if no such closing price on such date is published in The Wall
Street Journal (National Edition), the average of the closing bid and asked
prices on such date, as officially reported on the principal national securities
exchange on which such Capital Stock is then listed or admitted to trading; or
(b) if such Capital Stock is not then listed or admitted to trading on any
national securities exchange but is designated as a national market system
security by the National Association of Securities Dealers, Inc., the last
trading price of such Capital Stock on such date; or (c) if there shall have
been no trading on such date or if such Capital Stock is not designated as a
national market system security by the National Association of Securities
Dealers, Inc., the average of the reported closing bid and asked prices of such
Capital Stock on such date as shown by the National Market System of the
National Association of Securities Dealers, Inc. Automated Quotations System and
reported by any member firm of the New York Stock Exchange selected by the
Corporation; or (d) if none of (a), (b) or (c) is applicable, a market price per
share determined by the Board of Directors.

                  "NASDAQ" shall mean The Nasdaq Stock Market, Inc.

                  "Person" means any individual, firm, corporation, partnership,
limited liability company, trust, incorporated or unincorporated association,
joint venture, joint stock company, governmental body or other entity of any
kind.

                  "Price Per Share" means $1.50 (subject to anti-dilution
adjustment for stock splits of , combinations of and capital reorganizations
with respect to the Series E Preferred Stock).

                  "Rights Offering" shall mean a rights offering for an
aggregate amount of up to $21,000,000 of shares of Series E Preferred Stock
pursuant to which the Corporation will distribute transferable rights to the
Corporation's holders of Common Stock as contemplated by the Convertible Note
Purchase and Exchange Agreement, dated November 18, 2003, among the Corporation
and certain other parties thereto.

                  "Rights Shares" means the shares of Series E Preferred Stock
issuable upon exercise of the Series E Purchase Rights and the shares of the
Common Stock issuable upon conversion of such shares of Series E Preferred
Stock.

                  "Securities Act" means the Securities Act of 1933, as amended,
and the rules and regulations of the Commission promulgated thereunder.

                  "Series D Liquidation Payment" shall have the meaning ascribed
to it in the Amended and Restated Certificate of Determination of Preferences of
Series D Preferred Stock if and when approved by the requisite stockholders of
the Corporation and duly filed with the Secretary of State of the State of
California.

                  "Series D Preferred Stock" shall have the meaning ascribed to
it in the Amended and Restated Certificate of Determination of Preferences of
Series D Preferred Stock if and when

                                       13
<PAGE>

approved by the requisite stockholders of the Corporation and duly filed with
the Secretary of State of the State of California.

                  "Series E Accreted Value" shall mean as of any date, with
respect to each share of Series E Preferred Stock, the Price Per Share plus the
amount of dividends that have accrued from the Series E Closing Date to the then
most recent Series E Accrual Date pursuant to Section 3(a) of this Certificate
of Determination.

                  "Series E Automatic Redemption Date" shall have the meaning
ascribed to it in Section 5(b) hereof.

                  "Series E Closing Date" means _____________, 2003.

                  "Series E Conversion Price" shall mean $1.50, as adjusted
pursuant to Section 7(c).

                  "Series E Liquidation Payment" shall mean, with respect to
each share of Series E Preferred Stock, those amounts payable pursuant to
Section 4(a)(i) or Section 4(b)(i), as the case may be.

                  "Series E Optional Redemption Date" shall have the meaning
ascribed to it in Section 5(a)(ii) hereof.

                  "Series E Optional Redemption Measurement Window" shall have
the meaning ascribed to it in Section 5(a)(i) hereof.

                  "Series E Optional Redemption Period" shall have the meaning
ascribed to it in Section 5(a)(i) hereof.

                  "Series E Optional Redemption Price" shall have the meaning
ascribed to it in Section 5(a)(i) hereof.

                  "Series E Preferred Stock" shall have the meaning ascribed to
it in Section 1 hereof.

                  "Series E Purchase Rights" means those rights to purchase
Series E Preferred Stock issued in the Rights Offering.

                  "Series E Redemption Price" shall have the meaning ascribed to
it in Section 5(b) hereof.

                  "Stock Option Plans" means the Corporation's stock option
plans and employee purchase plans approved by the Board of Directors, pursuant
to which shares of restricted stock and options to purchase shares of Series E
Preferred Stock and/or Common Stock are reserved and available for grant to
officers, directors, employees and consultants of the Corporation.

                                   * * * * * *

                                       14
<PAGE>

         3.       This Certificate of Determination has been duly approved by
the Board of Directors. The authorized number of shares of Preferred Stock of
the Corporation is [__________], of which one share constitutes the Special
Voting Share, which share has been issued, 75,000 shares constitute Series C
Participating Preferred Stock, none of which has been issued, [___________]
shares of Series D Preferred Stock, [all] of which have been issued, and
[__________] shares of Series E Preferred Stock, none of which has been issued.
The number of shares voting in favor of this Certificate of Determination
equaled or exceeded the vote required. The percentage vote required under the
Amended and Restated Articles of Incorporation in effect at the time of this
Certificate of Determination was more than 50% of the outstanding shares of
Series D Preferred Stock, voting separately as a class.

              [the remainder of this page intentionally left blank]

                                       15
<PAGE>

         The undersigned, William E. McGlashan, Jr. and Michael J. Zukerman, the
Chief Executive Officer and Chairman of the Board of Directors and Vice
President and Secretary, respectively, of Critical Path, Inc., declare under
penalty of perjury that the matters set out in the foregoing Certificate are
true of their own knowledge.

         Executed at San Francisco, California on this [__] day of [__________],
[____].

                                           _________________________________
                                          William E. McGlashan, Jr.,
                                          Chief Executive Officer and
                                          Chairman of the Board of Directors

                                          _________________________________
                                          Michael J. Zukerman,
                                          Senior Vice President, General Counsel
                                          and Secretary