<PAGE>
                                                                    EXHIBIT 4.11

                                ESCROW AGREEMENT

        ESCROW AGREEMENT, dated November 8, 2001 (this "Escrow Agreement"), by
and among General Atlantic Partners 74, L.P., a Delaware limited partnership,
GAP Coinvestment Partners II, L.P., a Delaware limited partnership, GapStar,
LLC, a Delaware limited liability company, Vectis CP Holdings, LLC , a Delaware
limited liability company, Cenwell Limited and Campina Enterprises Limited
(collectively, the "Purchasers"), Critical Path, Inc., a California Corporation
("Seller"), and Pillsbury Winthrop, LLP, as Escrow Agent (the "Escrow Agent").

        WHEREAS, the Purchasers and Seller are parties to the Stock and Warrant
Purchase and Exchange Agreement, dated the date hereof (the "Purchase
Agreement"), pursuant to which the (i) Purchasers are acquiring from Seller an
aggregate of 4,000,000 shares of Series D Cumulative Redeemable Convertible
Participating Preferred Stock, par value $0.001 per share, of Seller (the
"Series D Preferred Stock") and (ii) the GAP Purchasers (as defined in the
Purchase Agreement) are acquiring from the Seller warrants (the "Warrants"), to
purchase, at an exercise price of $1.05 per share, an aggregate of 2,500,000
shares of common stock, par value $0.001 per share, of Seller (the "Common
Stock");

        WHEREAS, the Purchase Agreement provides for the escrow hereby
established to be held by the Escrow Agent; and

        WHEREAS, capitalized terms used herein, unless otherwise indicated, have
the respective meanings ascribed to them in the Purchase Agreement.

        Accordingly, the parties agree as follows:

        1. Establishment of Escrow.

                1.1 Escrow Deposit.

                        1.1.1 On November 9, 2001, pursuant to (i) Section 2.1
of the Purchase Agreement, the Purchasers will deposit with the Escrow Agent
$29,735,502.50 representing the entire purchase price payable pursuant to
Section 2.1 for the Purchased Shares, (ii) Section 2.2 of the Purchase
Agreement, the GAP Purchasers will deposit with the Escrow Agent the GAP Sub
Notes in the aggregate face amount of $64,630,000 together with signed and
undated Note Powers for such GAP Sub Notes, and (iii) Section 2.3 of the
Purchase Agreement, the GAP Purchasers will deposit with the Escrow Agent
$1,000.00 representing the entire purchase price for the Warrants and (the items
in clause (i)-(iii) referred to collectively, as the "Purchasers' Deposit") to
be held and disbursed in accordance with the terms hereof.

                        1.1.2 On November 9, 2001, pursuant to Sections 2.1, 2.2
and 2.3 of the Purchase Agreement, Seller is depositing with the Escrow Agent
(i) stock certificates in definitive form representing the number of Purchased
Shares set forth opposite each Purchaser's name on Schedule 2.1 to the Purchase
Agreement, updated, but


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                                                                               2


registered in the name of such Purchasers, (ii) stock certificates in definitive
form representing the number of Exchange Shares set forth opposite each GAP
Purchaser's name on Schedule 2.2 to the Purchase Agreement, undated but
registered in the name of such GAP Purchaser, (iii) the GAP LP Warrant , (iv)
the GAP Coinvestment Warrant, and (v) the GapStar Warrant, (collectively, the
"Seller's Deposit" and, together with the Purchasers' Deposit, the "Deposit").

                        1.1.3 The Escrow Agent acknowledges receipt of and
agrees to accept the Deposit and establish and maintain a separate account for
each Purchaser's cash portion of the Deposit as provided herein (the "Escrow
Account").

                1.2 Escrow Fund. The cash portion of the Deposit, as from time
to time invested and reinvested as herein provided, less any distributions
pursuant hereto, is hereinafter referred to as the "Escrow Fund."

        2. Investment of Escrow Fund.

                2.1 Investment. The Escrow Agent shall invest any or all of the
Escrow Fund and any income or interest earned or accrued with respect thereto
only in time deposits and certificates of deposit of any commercial bank
incorporated in the United States of America of recognized standing having
capital and surplus in excess of $50,000,000. Except as otherwise provided in
Section 5.3, in no event shall the Escrow Agent have any liability for any
investment hereunder, including, without limitation, any loss of the principal
amount of any investment or in connection with the rate of return on any
investment.

                2.2 Distribution of Interest. All interest accrued from the date
hereof to and including the Escrow Release Date (as defined below) on
investments made pursuant to Section 2.1 shall be for the account of each of the
Purchasers. On the Escrow Release Date, the Escrow Agent shall distribute to
each of the Purchasers all interest then accrued for the account of each of the
Purchasers pursuant to this Section 2.2 and not theretofore distributed
hereunder.

        3. Distributions from the Escrow.

                3.1 Distributions.

                        3.1.1 Upon the satisfaction of the Escrow Release
Condition (as hereinafter defined) and the Nasdaq Escrow Approval Condition (as
hereinafter defined), the Purchasers shall execute and deliver to the Escrow
Agent a Certificate directing the Escrow Agent to take the action specified in
Section 3.1.2(a). Upon the satisfaction of the Escrow Release Condition, but not
the Nasdaq Escrow Approval Condition, Purchasers shall execute and deliver to
the Escrow Agent a Certificate directing the Escrow Agent to take the action
specified in Section 3.1.2(b). If subsequent to the delivery of the Certificate
referred to in the previous sentence and on or prior to March 31, 2002, the
Nasdaq Escrow Approval Condition is satisfied, the GAP Purchasers shall execute
and deliver to the Escrow Agent a Certificate directing the Escrow Agent to take
the action specified in Section 3.1.2(c).


<PAGE>
                                                                               3


                        3.1.2 (a) Upon receipt by the Escrow Agent of a
Certificate signed by the GAP Purchasers stating that the Escrow Release
Condition and the Nasdaq Escrow Approval Condition have occurred, the Escrow
Agent shall promptly, but in any case within 24 hours of receipt, (i) distribute
to Seller the Purchasers' Deposit and (ii) deliver to the Purchasers the
Seller's Deposit and the interest on the Escrow Fund payable pursuant to Section
2.2 of this Agreement.

                                (b) Upon receipt by the Escrow Agent of a
Certificate signed by the GAP Purchasers stating that the Escrow Release
Condition has occurred but the Nasdaq Escrow Approval Condition has not
occurred, the Escrow Agent shall promptly, but in any case within 24 hours, (i)
distribute to the Seller the Purchasers' Deposit, less the Consideration
Holdback Amount (as defined below) and (ii) deliver to the Purchasers the
Seller's Deposit, less the Purchased Shares Holdback (as defined below) and the
interest on the Escrow Fund payable pursuant to Section 2.2 of this Agreement.

                                (c) Upon receipt by the Escrow Agent of a
Certificate signed by the GAP Purchasers stating that the Nasdaq Escrow Approval
Condition has occurred, the Escrow Agent shall promptly, but in any case within
24 hours, (i) distribute to the Seller the Consideration Holdback Amount and
(ii) deliver to the GAP Purchasers the Purchased Shares Holdback.

                        3.1.3 For purposes of this Agreement, the "Escrow
Release Condition" shall mean the entry on or before January 31, 2002 of a final
order by District Court Judge William H. Orrick, not subject to further review,
approving an executed, final, Stipulation and Agreement of Settlement in the
litigation entitled In Re Critical Path Inc. Securities Litigation (the
"Actions") and that (A) provides for the certification of the "Class" (as
defined in paragraph 1 of the MOU), (B) contains terms and conditions for the
payment of cash and warrants to purchase the Common Stock to the Class that do
not differ from the amounts set forth in paragraph 2 of the MOU and (C)
dismisses the Action with prejudice as set forth in paragraph 3 of the MOU and
provides for a broad form general release for the Defendants and the other
parties as provided in paragraph 3 of the MOU.

                        3.1.4 "Escrow Release Date" shall mean the date upon
which the notice specified in the first sentence of Section 3.1.1 is delivered
by the GAP Purchasers.

                        3.1.5 "Nasdaq Escrow Approval Condition" means the
earlier to occur of (i) the date upon which the Company obtains written
confirmation from Nasdaq that the approval of a majority of the Company's
stockholders, present in person or proxy at a properly convened meeting of the
Company's stockholders ("Stockholder Approval") to the issuance of the shares of
Preferred Stock to the GAP Purchasers is not required under the applicable
Nasdaq rules and regulations and (ii) the date upon which the Company
consummates all action required by the Nasdaq and applicable California law to
obtain Stockholder Approval for the issuance to the GAP Purchasers of the
portion of the shares of Series D Preferred Stock that constitute the


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                                                                               4


amount of shares of Series D Preferred Stock (determined assuming conversion of
all of the shares of Series D Preferred Stock) in excess of 19.9% of the
outstanding shares of the Common Stock on the date hereof.

                        3.1.6 "Consideration Holdback Amount" shall mean a total
of $19,220,960, consisting of $9,485,464 aggregate purchase price amount (and
$24,265,101 aggregate face amount) of GAP Sub Notes and $9,735,496 of cash.

                        3.1.7 "Purchased Shares Holdback" shall mean a total of
1,397,888 shares of Preferred Stock.

                        3.1.8 On the earlier of (i) receipt of a joint notice
executed by all of the Purchasers and Seller or (ii) January 31, 2002 (the
"Escrow Termination Date"), the Escrow Agent shall return the Purchaser's
Deposit to the Purchasers and the Seller's Deposit to Seller.

                        3.1.9 If the Nasdaq Escrow Approval Condition has not
been satisfied by April 30, 2002, the Escrow Agent shall return the
Consideration Holdback Amount to the GAP Purchasers, together with any remaining
interest in the Escrow Account and return the Purchased Shares Holdback to the
Seller.

                3.2 Tax Reporting. Seller and each of the Purchasers
shall provide the Escrow Agent with its Tax Identification Number (TIN) as
assigned by the Internal Revenue Service. All interest or other income earned
under this Escrow Agreement shall be allocated and paid as provided herein and
reported by the recipient to the Internal Revenue Service as having been so
allocated and paid.

        4. Termination of this Escrow Agreement. This Escrow Agreement shall
terminate upon the distribution or return of all of the Purchasers' Deposit, all
of Seller's Deposit and all other sums and documents held by the Escrow Agent
pursuant to this Escrow Agreement.

        5. Duties of Escrow Agent.

                5.1 Duties Limited. The Escrow Agent shall perform only the
duties expressly set forth herein, and shall not have any liability under, or
duty to inquire into, the terms and provisions of any other agreement, including
but not limited to the Purchase Agreement, except as expressly set forth herein,
in performing its duties hereunder. Except as to the due execution and delivery
of this Escrow Agreement by a duly authorized officer, the Escrow Agent has no
responsibility as to the validity of this Escrow Agreement or any document
related thereto.

                5.2 Reliance. The Escrow Agent may rely upon, and shall incur no
liability for acting or refraining from acting upon, any written notice,
instruction, request, consent, certificate, statement or other document
furnished to it pursuant to this Escrow Agreement and believed by it to be
genuine and to have been signed or presented by the proper party or parties, and
the Escrow Agent shall be under no duty to inquire into or investigate the
validity, accuracy or content of any such document.


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                                                                               5


                5.3 Good Faith. In no event shall the Escrow Agent have any
liability for any error of judgment or for any act done or omitted by it in good
faith, or for any mistake of fact or law, or for anything which it may do or
refrain from doing hereunder, except for its own gross negligence or willful
misconduct arising out of or in connection with this Escrow Agreement. The
Purchasers and Seller agree to indemnify the Escrow Agent for, and defend and
hold it harmless against, any loss, liability or expense arising out of or in
connection with its actions as Escrow Agent hereunder, including the reasonable
costs and expenses incurred in defending any such claim of liability, except
that none of the Purchasers or the Seller shall be liable for any loss,
liability or expense incurred on account of the gross negligence or willful
misconduct on the part of the Escrow Agent. The Escrow Agent may consult with
counsel from time to time and the opinion of such counsel shall be full and
complete authorization and protection in respect of any action taken or omitted
to be taken by the Escrow Agent hereunder or in good faith and in accordance
with the opinion of such counsel. The reasonable fees and disbursements of such
counsel shall be promptly paid one half by the Purchasers and one half by Seller
pursuant to the provisions of Section 7 hereof.

                5.4 Limited Notice. The Escrow Agent shall be deemed to have no
notice of, or duties with respect to, any agreement or agreements (whether or
not a copy thereof is delivered to the Escrow Agent), other than as expressly
set forth herein.

                5.5 Limited Actions. The Escrow Agent shall not take any action
by reason of any notice or instruction given by any of the parties or by any
other person, firm or corporation, except only (i) such notices or instructions
as are herein specifically provided for and (ii) orders or process of any court
entered or issued with competent jurisdiction. In the event that the Escrow
Agent shall be uncertain as to its duties or rights hereunder, it shall be
entitled to refrain from taking any action until it shall be directed otherwise
in writing by each of the Purchasers and Seller or by an order of a court of
competent jurisdiction.

                5.6 Conflicts.

                        5.6.1 In the event that any of the terms and provisions
of any other agreement between any of the parties conflict or are inconsistent
with any of the terms and provisions of this Escrow Agreement, the terms and
provisions of this Escrow Agreement shall govern and control in all respects the
duties and liabilities of the Escrow Agent.

                        5.6.2 In the event that the Escrow Agent shall be
uncertain as to its duties or rights hereunder or shall receive instructions,
claims or demands from any party hereto which, in its opinion, conflict with any
of the provisions of this Agreement, it shall be entitled to refrain from taking
any action and its sole obligation shall be to keep safely all property held in
escrow until it shall be directed otherwise in writing by all of the other
parties hereto or by a final order or judgment of a court of competent
jurisdiction.


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                                                                               6


        6. Resignation; Successor Escrow Agent.

                6.1 Resignation. The Escrow Agent may resign at any time by
giving 30 days' prior written notice of such resignation to the Purchasers and
Seller. On the 30th day following delivery of such notice, the Escrow Agent
shall have no further obligation hereunder except to hold the Escrow Fund and
any other amounts and documents held by it pursuant to this Escrow Agreement as
depositary. After resignation, the Escrow Agent shall have no further obligation
to invest amounts then in the Escrow Fund (absent written instructions with
respect thereto executed by the Seller and the Purchasers) and shall not take
any action until the Purchasers and Seller have jointly designated a successor
escrow agent. If the Purchasers and Seller are unable to agree upon a successor
escrow agent within 30 days of receipt of notice from the Escrow Agent, the
Escrow Agent may designate its successor, and if the Escrow Agent declines to
designate its successor, the Purchasers shall designate the successor escrow
agent. The Escrow Agent shall promptly deliver the Escrow Fund and any other
amounts and documents held by it pursuant to this Escrow Agreement to such
successor escrow agent and shall thereafter have no further obligations
hereunder. Upon receipt of the Escrow Fund and other amounts and documents, the
successor escrow agent shall thereupon be bound by all of the provisions hereof.

                6.2 Termination. The Purchasers and Seller acting jointly may
terminate the appointment of the Escrow Agent hereunder upon notice specifying
the date upon which such termination shall take effect. In the event of such
termination, the Purchasers and Seller shall jointly appoint and designate in
such termination notice a successor escrow agent and the Escrow Agent shall turn
over to such successor escrow agent the Escrow Fund and any other amounts and
documents held by it pursuant to this Escrow Agreement. Upon receipt of the
Escrow Fund and other amounts and documents, the successor escrow agent shall
thereupon be bound by all of the provisions hereof, and the Escrow Agent shall
have no further obligations hereunder.

        7. Fees and Expenses of Escrow Agent. The Purchasers and Seller shall
each pay directly to the Escrow Agent one half of the Escrow Agent's reasonable
fees for the Escrow Agent's services hereunder and all expenses, disbursements
and advances (including reasonable attorneys' fees) incurred in carrying out the
Escrow Agent's duties hereunder (the "Escrow Agent's Fees").

        8. Miscellaneous.

                8.1 Notices. Any notice or other communication required or
permitted hereunder shall be in writing and shall be delivered personally,
telegraphed, sent by facsimile transmission, overnight delivery service or
certified, registered or express mail, postage prepaid. Any such notice shall be
deemed given when so delivered personally, telegraphed or sent by facsimile
transmission, or by overnight delivery service, one day after the date of
deposit to such overnight delivery service or, if mailed, three days after the
date of deposit in the United States mail, as follows:


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                                                                               7


                      if to Seller:

                      Critical Path, Inc.
                      532 Folsom Street
                      San Francisco, CA 94105
                      Attention:  Chief Financial Officer
                      Telecopy:  (415) 808-8898

                      with a copy to:

                      Pillsbury Winthrop LLP
                      P.O. Box 7880
                      San Francisco, CA 94105-7880
                      Attention:  Gregg F. Vignos, Esq.
                      Telecopy:  (415) 983-1200

                      if to the GAP Purchasers:

                      c/o General Atlantic Service Corporation
                      3 Pickwick Plaza
                      Greenwich, CT 06830
                      Telecopy:  (203) 622-8818
                      Attention:  Matthew Nimetz

                      with a copy to:

                      Paul, Weiss, Rifkind, Wharton & Garrison
                      1285 Avenue of the Americas
                      New York, New York  10019-6064
                      Attention: Douglas A. Cifu, Esq.
                      Telecopy:  (212) 757-3990

                      if to Vectis CP Holdings, LLC:

                      c/o Vectis Group
                      117 Greenwich Street
                      San Francisco, CA 94111
                      Telecopy:  (415) 352-5310
                      Attention:  Matthew Hobart

                      with a copy to:

                      Kirkland & Ellis
                      153 East 53rd Street
                      New York, NY 10022-4675
                      Telecopy:  (212) 446-4900
                      Attention:  Michael Movsovich, Esq.


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                                                                               8


                      if to Cenwell Limited:

                      c/o 12th Floor
                      Cheung Kong Center
                      2 Queen's Road Central
                      Hong Kong
                      Telecopy:  852-2485-2057
                      Attention:  Mr. Edmond lp.

                      if to Campina Enterprises Limited:

                      c/o 22nd Floor
                      Hutchison House
                      10 Harcourt Road
                      Hong Kong
                      Telecopy:  852-2128-1778
                      Attention:  Company Secretary

                      if to the Escrow Agent:

                      Pillsbury Winthrop LLP
                      50 Fremont Street
                      San Francisco, CA 94104
                      Attention:  Gregg F. Vignos, Esq.
                      Telecopy:  415-983-1200

Any party may by notice given in accordance with this Section 8.1 to the other
parties designate another address for receipt of notices hereunder. In the event
that the Escrow Agent, in its sole discretion, shall determine that an emergency
exists, the Escrow Agent may use such other means of communication as the Escrow
Agent deems advisable. If any notice is required to be given to both the Escrow
Agent and another party, such notice shall be given in a manner that results in
the same effective date for each such notice.

                        8.1.1 In the event funds transfer instructions are given
(other than in writing at the time of execution of this Escrow Agreement),
whether in writing, by telecopier or otherwise, the Escrow Agent is authorized
to seek confirmation of such instructions by telephone call-back to the person
or persons designated on Schedule II hereto, and the Escrow Agent may rely upon
the confirmations of anyone purporting to be the person or persons so
designated. The persons and telephone numbers for call-backs may be changed only
in a writing actually received and acknowledged by the Escrow Agent. The parties
to this Agreement acknowledge that such security procedure is commercially
reasonable.

                        8.1.2 It is understood that the Escrow Agent and the
beneficiary's bank in any funds transfer may rely solely upon any account
numbers or


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                                                                               9


similar identifying number provided either of the other parties hereto to
identify (i) the beneficiary, (ii) the beneficiary's bank, or (iii) an
intermediary bank. The Escrow Agent may apply any of the escrowed funds for any
payment order it executes using any such identifying number, even where its use
may result in a person other than the beneficiary being paid, or transfer of
funds to a bank other than the beneficiary's bank, or an intermediary bank
designated.

                8.2 Entire Agreement. This Escrow Agreement is entered into and
delivered pursuant to the Purchase Agreement and sets forth the entire agreement
among the parties with respect to the subject matter hereof and supersedes all
prior agreements, written or oral, with respect thereto.

                8.3 Governing Law. This Escrow Agreement shall be governed and
construed in accordance with the laws of the State of New York without regard to
its principles of conflicts of laws.

                8.4 Jurisdiction; Venue. Each of the parties hereto by its
execution hereof:

                        8.4.1 irrevocably submits to the jurisdiction of the
state courts of the State of New York and to the jurisdiction of the United
States District Court for the Southern District of New York, for the purpose of
any suit, action or other proceeding arising out of or based on this Agreement
or the subject matter hereof; and

                        8.4.2 waives to the extent not prohibited by applicable
law, and agrees not to assert, by way of motion, as a defense or otherwise, in
any such proceeding brought in any of the above-named courts, any claim that it
is not subject personally to the jurisdiction of such courts, that its property
is exempt or immune from attachment or execution, that any such proceeding
brought in an inconvenient forum, that the venue of such proceeding is improper,
or that this Agreement, or the subject matter hereof, may not be enforced in or
by such court.

The parties hereto hereby agree that any action brought under this Agreement
shall be brought in one of the above-mentioned courts.

The parties hereto hereby consent to service of process in any such proceeding
in any manner permitted by the laws of the State of New York, and agree that
service of process by registered or certified mail, return receipt requested, at
its address specified in or pursuant to Section 8.5 is reasonably calculated to
give actual notice.

                8.5 Binding Effect. This Escrow Agreement shall be binding upon
and inure to the benefit of the parties and their respective heirs, legal
representatives, successors and assigns.

                8.6 Waivers and Amendments. This Escrow Agreement may be
amended, modified, superseded, cancelled, renewed or extended, and the terms or
conditions hereof may be waived, only by a written instrument signed by the
parties, or, in the case of a waiver, by the party waiving compliance. No delay
on the part of any


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                                                                              10


party in exercising any right, power or privilege hereunder shall operate as a
waiver thereof, nor shall any waiver on the part of any party of any right,
power or privilege hereunder, nor any single or partial exercise of any right,
power or privilege hereunder, preclude any other or further exercise thereof or
the exercise of any other right, power or privilege hereunder.

                8.7 Counterparts. This Escrow 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.

                8.8 Further Assurances. Each of the parties shall execute such
documents and other papers and take such further actions as may be reasonably
required or desirable to carry out the provisions hereof and the transactions
contemplated hereby.

                8.9 Variations in Pronouns. All pronouns and any variations
thereof refer to the masculine, feminine or neuter, singular or plural, as the
identity of the person or persons may require.

                8.10 Headings. The headings in this Escrow Agreement are for
reference purposes only and shall not in any way affect the meaning or
interpretation of this Escrow Agreement.

                8.11 Conflict Waiver. Each party to this Escrow Agreement
acknowledges that the Escrow Agent is counsel for the Seller and has in the past
and will in the future perform legal services for Seller in matters related to
and unrelated to this Escrow Agreement and the parties hereto hereby (i)
acknowledge that they have had an opportunity to ask for information relevant to
this disclosure; (ii) acknowledge that the Escrow Agent represented the Seller
in the transaction contemplated by this Escrow Agreement and has not represented
any Purchaser in connection with such transaction; and (iii) give its informed
written consent to the representation of the Seller in connection with the
Purchase Agreement; and the transactions contemplated thereby, including
litigation arising thereunder.


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                                                                              11


                IN WITNESS WHEREOF, the parties have caused this Escrow
Agreement to be executed on the date first written above.

                                    GENERAL ATLANTIC PARTNERS 74, L.P.
                                    By: GENERAL ATLANTIC PARTNERS, LLC,
                                            its General Partner

                                    By:    /s/ William Ford
                                        ----------------------------------------
                                    Name:
                                    Title: A Managing Member

                                    Address for Notice to General Atlantic
                                    Partners 74, L.P., GAPp Coinvestment
                                    Partners II, L.P. and GapStar, LLC:

                                    c/o General Atlantic Service Corporation
                                    3 Pickwick Plaza
                                    Greenwich, CT 06830
                                    Attn: Matthew Nimetz
                                    Tel: 203-629-8600
                                    Fax: 203-622-8818

                                    With copies to:

                                    Paul, Weiss, Rifkind, Wharton & Garrison
                                    1285 Avenue of the Americas
                                    New York, NY 10019-60064
                                    Attn: Douglas A. Cifu, Esq.
                                    Tel:  212-373-3426
                                    Fax:  212-757-3990

                                    GAP COINVESTMENT PARTNERS II, L.P.

                                    By:    /s/ William Ford
                                        ----------------------------------------
                                    Name:
                                    Title: A General Partner

                                    GAPSTAR, LLC

                                    By: GENERAL ATLANTIC PARTNERS, LLC,
                                            its Managing Member

                                    By:    /s/ William Ford
                                        ----------------------------------------
                                    Name:
                                    Title: A Managing Member


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                                                                              12


                                    CENWELL LIMITED

                                    By:     /s/ Cenwell
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    Address for Notice to Cenwell Limited:

                                    c/o 12th Floor
                                    Cheung Kong Center
                                    2 Queen's Road Central
                                    Hong Kong
                                    Attn:  Mr. Edmond lp.
                                    Fax:  852-2845-2057

                                    CAMPINA ENTERPRISES LIMITED

                                    By:     /s/ Campina
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    c/o 22nd Floor
                                    Hutchison House
                                    10 Harcourt Road
                                    Hong Kong
                                    Attn:  Company Secretary
                                    Fax:  852-2128-1778

                                    VECTIS CP HOLDINGS, LLC,
                                    a Delaware limited liability company
                                    By: VECTIS GROUP LLC,
                                            its Managing Member

                                    By:     /s/ Matthew Hobart
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    Address for Notice to Vectis CP Holdings,
                                    LLC:

                                    117 Greenwich Street
                                    San Francisco, CA 94111
                                    Attn: Matthew Hobart
                                    Fax: 415-352-5310


<PAGE>
                                                                              13


                                    CRITICAL PATH, INC.


                                    By:     /s/ Laureen DeBuono
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    Address for Notice to Critical Path, Inc.:

                                    532 Folsom Street
                                    San Francisco, CA 94105
                                    Attn:  Chief Financial Officer
                                    Fax: (415) 808-8898

                                    With copies to:

                                    Pillsbury Winthrop LLP
                                    P.O. Box 7880
                                    San Francisco, CA 94120-7880
                                    Attention: Gregg F. Vignos
                                    Tel: 415-983-1000
                                    Fax: 415-983-1200

                                    PILLSBURY WINTHROP LLP,
                                    Escrow Agent

                                    By:     /s/ Gregg Vignos
                                        ----------------------------------------
                                    Name:
                                    Title:

                                    Address for Notice to the Escrow Agent:

                                    Pillsbury Winthrop LLP
                                    P.O. Box 7880
                                    San Francisco, CA 94120-7880
                                    Attention: Gregg F. Vignos
                                    Tel: 415-983-1000
                                    Fax: 415-983-1200