Exhibit 5.1

OPINION OF JEFFREY D. ADELMAN








                               December 29, 2000

j2 Global Communications, Inc.
6922 Hollywood Boulevard
Hollywood, California  90028

Ladies and Gentlemen:

          I have acted as Counsel to the Company in connection with the
registration of 7,351,448 shares of the Company's par value US $0.01 per share
(the "Shares") under the Securities Act of 1933, as amended ("Securities Act"),
as described in the registration statement on Form S-3 (the "Registration
Statement") filed with the United States Securities and Exchange Commission (the
"Securities and Exchange Commission") on or about the date hereof.

          For the purposes of giving this opinion, I have examined the following
documents:

          (1)  a copy of the final form of the Registration Statement as
               provided to me by the Company on December 28, 2000;

          (2)  a copy of the certificate of merger, duly certified as filed on
               November 29, 2000 by the Secretary of State for the State of
               Delaware; and

          (3)  a copy of resolutions duly adopted by the Board of Directors of
               the Company on July 12, 2000.

I have also examined and relied as to factual matters upon the originals, or
copies, certified or otherwise identified to my satisfaction, of the Certificate
of Incorporation and By-laws of the Company, certificates of public officials,
certificates of officers of the Company, certain agreements to which the Company
is a party and such other records, documents, certificates and instruments, and
have made such other investigations, as in my judgment are necessary or
appropriate to enable me to render the opinions expressed below.

          I have assumed that (i) the resolutions in writing referred to herein
are full and accurate records of resolutions passed in accordance with the
by-laws of the Company and that such resolutions have not been amended or
rescinded and are in full force and effect, (ii) there is no provision of the
law of any jurisdiction, other than Delaware, which would have any implication
in relation to the opinion expressed herein, (iii) the Shares fall within the
existing authorized share capital of the Company, and (iv) no resolution has
been passed by the shareholders of the Company to limit or otherwise fetter the
powers granted to the directors of the Company by the by-laws of the Company to
issue any unissued shares of the Company on such terms and conditions as they
may determine.

          I am licensed to practice law only in the State of Michigan. However,
I have not in connection with this opinion made an investigation of the laws of
any jurisdiction except the General Corporation Law of the State of Delaware,
and nothing in this opinion should be or shall be construed otherwise. This
opinion is limited solely to the laws of the General Corporation Law of the
State of Delaware. Subject as mentioned below, this opinion is issued solely for
your benefit and is not to be relied upon by any other person, firm or entity or
in respect of any other matter.

          On the basis of and subject to the foregoing, I am of the opinion that
the Shares have been duly authorized, issued, fully paid and are non-assessable.

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          I hereby consent to the filing of this opinion as an exhibit to the
Registration Statement. In giving such consent I do not thereby admit that I
come within the category of persons whose consent is required under Section 7 of
the Securities Act, or the Rules and Regulations of the Securities and Exchange
Commission thereunder.

                                    Very truly yours,

                                    /s/ Jeffrey D. Adelman
                                    ----------------------------
                                    Jeffrey D. Adelman
                                    General Counsel
                                    j2 Global Communications, Inc.

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