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                                                                   EXHIBIT 10.1


                   FIRST AMENDMENT TO EMAIL SERVICES AGREEMENT

        The following amendment (the "Amendment") is entered into by and between
Critical Path, Inc. and ICQ, Inc. (together the "Parties) as of this 7th day of
May, 1999.

WHEREAS, the Parties have entered into that certain Email Services Agreement
dated as of January 29, 1999.

WHEREAS, the Parties now desire to amend the Agreement as provided in this
Amendment below.

WHEREAS, the Parties now desire to amend the Agreement as provided in this
Amendment below.

NOW THEREFORE, for good and valuable consideration the sufficiency of which is
hereby acknowledged by the Parties, the Parties agree as follows:

        1. Definitions. Any capitalized term not otherwise defined herein shall
have the meanings assigned to them in the Agreement.

        2. Amendment. The Agreement shall be amended so that the existing
Section 9 shall be deleted in its entirety and replaced with the following:

        9. EXCLUSIVITY

Except as provided in this Section 9, the parties agree that the relationship
created by this Agreement shall be non-exclusive, and each of the parties may
enter into the same or a similar relationship with one or more third parties.
Without limiting the generality of the foregoing, ICQ shall be free to enter
into agreements with third parties for the use of integration of other web-based
email software and services with the ICQ Service, and CP shall be free to enter
into agreements with third parties pursuant to which it provides email products
and services to such third parties. However, notwithstanding the foregoing, CP
agrees that, during the term of this Agreement, it shall not integrate any email
or email related service it provides to any entity with any instant messaging,
or similar or related online, real time messaging product ("Instant Messaging
Product") of that entity (or of an affiliate of that entity), nor shall CP
integrate any Instant Messaging Program other than ICQ instant messaging product
into any email service provided by CP to end users directly or to more than one
particular customer of CP on a case-by-case basis (with any such integration for
the latter still being subject to the next following sentence). Further, CP
agrees that it will not assist any of its customers or partners in integrating
Instant Messaging Products other than ICQ instant messaging products into any
email product or service provided by CP or its affiliates, unless such customer
or partners insists upon such assistance after CP has used commercially
reasonably efforts to persuade such customer or partner to instead use ICQ
instant messaging products and


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services. During the term of this Agreement, CP will promote ICQ as CP's
preferred integrated instant messaging service and product.

        3. No Other Changes. Except as expressly amended herein, the provisions
of the Agreement shall remain in full force and effect and nothing in this
Amendment shall be constructed as a waiver of any of the rights and obligations
of the Parties under the Agreement.

        4. Governing Law. This Amendment shall be interpreted, constructed and
enforced in all respects in accordance with the laws of the Commonwealth of
Virginia except for it conflicts of laws principles.

        5. Counterparts. This Amendment may be executed in the counterparts,
each of which will constitute an original but all of which when taken together
will constitute one instrument.

        In witness whereof, the Parties have executed this Amendment on the date
first written above.



ICQ, INC.                                  CRITICAL PATH, INC.


By:  /s/                                   By:  /s/
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Name:                                      Name:
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Title:                                     Title:
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