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                                                                  EXHIBIT 10(21)

                           COMVERSE TECHNOLOGY, INC.
                             1996 STOCK OPTION PLAN
1.   Purpose.
     ------- 

     The purpose of this 1996 Stock Option Plan (the "Plan") is to induce key
personnel, including employees, directors, independent contractors, and other
persons rendering valued services, to remain in the employ or service of
Comverse Technology, Inc. (the "Company"), and its present and future subsidiary
corporations (each of which is hereinafter referred to as a "Subsidiary"), to
attract new personnel and to encourage such personnel to secure or increase on
reasonable terms their stock ownership in the Company.  The Board of Directors
of the Company (the "Board") believes that the granting of options (the
"Options") under the Plan will promote continuity of management and increased
incentive and personal interest in the welfare of the Company by those who are
or may become primarily responsible for shaping and carrying out the long range
plans of the Company and securing its continued growth and financial success.
Options granted hereunder are intended to be either (a) "incentive stock
options" (which term, when used herein, shall have the meaning ascribed thereto
by the provisions of Section 422(b) of the Internal Revenue Code of 1986, as
amended (the "Code")) or (b) options which are not incentive stock options or
(c) a combination thereof, as determined by the Committee (the "Committee")
(referred to in Section 5 hereof) at the time of the grant thereof.

2.   Effective Date of the Plan.
     -------------------------- 

     The Plan became effective on October 31, 1996, by resolution of the Board,
subject to ratification of the Plan by the vote of the holders of a majority of
the outstanding shares of the common stock, $0.10 par value, of the Company (the
"Common Stock") present in person or by proxy at the 1996 Annual Meeting of
Shareholders of the Company.

3.   Stock Subject to Plan.
     --------------------- 

     1,000,000 of the authorized but unissued shares of the Common Stock are
hereby reserved for issue upon the exercise of Options; provided, however, that
the number of shares so reserved may from time to time be reduced to the extent
that a corresponding number of issued and outstanding shares of the Common Stock
are purchased by the Company and set aside for issue upon the exercise of
Options.  If any Options expire or terminate for any reason without having been
exercised in full, the unpurchased shares subject thereto shall again be
available for the purposes of the Plan.

4.   Administration.
     -------------- 

     The Plan shall be administered by the Committee referred to in Section 5
hereof.  If a Committee shall not be so established, the Board shall perform the
duties and functions ascribed herein to the Committee.  Subject to the express
provisions of the Plan, the Committee shall have complete authority, in its
discretion, to interpret the Plan, to prescribe, amend and rescind rules and
regulations relating to it, to determine the terms and provisions of the
respective option agreements (which need not be identical), to determine the
individuals (the "Participants") to whom and the times and the prices at which
Options shall be granted, to establish the option periods, the number of shares
of the Common Stock to be subject to each Option, whether each Option shall be
exercisable immediately or in installments and, if in installments, the time and
size thereof, whether each Option shall be an incentive stock option or an
Option which is not an incentive stock option, and to make all other
determinations necessary or advisable for the administration of the Plan.  In
making such determinations, the Committee may take into account the nature of
the services rendered by the respective Participants, their present and
potential contributions to the success of the Company and the Subsidiaries and
such other factors as the Committee, in its discretion, shall deem relevant.
The Committee's determination on all of the matters referred to in this Section
4 shall be conclusive.
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5.   Committee.
     --------- 

     The Committee shall consist of at least three individuals who may, but need
not, be members of the Board and all of whom shall be "disinterested persons"
within the meaning of Rule 16b-3(c)(2)(i) promulgated under the Securities
Exchange Act of 1934, as amended.  The Committee shall be appointed by the
Board, which may at any time and from time to time remove any member of the
Committee, with or without cause, appoint additional members of the Committee
and fill vacancies, however caused, in the Committee.  A majority of the members
of the Committee shall constitute a quorum.  All determinations of the Committee
shall be made by a majority of its members.  Any decision or determination of
the Committee reduced to writing and signed by all of the members of the
Committee shall be fully as effective as if it had been made at a meeting duly
called and held.

6.   Eligibility.
     ----------- 

     A.   An Option which is an incentive stock option may be granted only to
key employees of the Company or a Subsidiary.

     B.   An Option which is not an incentive stock option may be granted only
to key employees of the Company or a Subsidiary, independent contractors hired
by the Company or a Subsidiary and, upon the terms and subject to the conditions
set forth in paragraph C of this Section, members of the Board who are not
employees of the Company or a Subsidiary.

     C.   Each director of the Company who is not an employee of the Company or
any Subsidiary, who does not receive compensation from the Company or any
Subsidiary in any capacity other than as a director of the Company and whose
membership on the Board is not attributable to any contract between the Company
and such director or any other entity with which such director is affiliated,
shall receive in each fiscal year of the Company Options to purchase 6,000
shares of Common Stock having an option price per share equal to the fair market
value of a share of Common Stock determined (in accordance with Paragraph C of
Section 7) as of the date two business days after the publication of the audited
year-end financial statements of the Company for the immediately preceding
fiscal year, such Options to be forfeited to the extent of 1,200 shares per
meeting in the event that such director, during the year of grant, fails to
attend, in the aggregate, at least five meetings of the Board and any committees
of the Board of which such director is a member; provided, however, that during
the continuation of the Company's previously-adopted Stock Option Plans, options
granted thereunder shall be deemed to be granted under the Plan for the purposes
of this Section 6.

7.   Option Prices.
     ------------- 

     A.   The initial per share option price of any Option which is an incentive
stock option shall not be less than the fair market value of a share of the
Common Stock on the date of grant; provided, however, that, in the case of a
Participant who owns more than 10% of the total combined voting power of the
Common Stock at the time an incentive stock option is granted to him, the
initial per share option price shall not be less than 110% of the fair market
value of the Common Stock.

     B.   The initial per share option price of any Option which is not an
incentive stock option shall not be less than $0.10; provided, that the initial
per share option price of any Option granted to a member of the Board who is not
an employee of the Company or any Subsidiary shall be fixed in accordance with
paragraph C of Section 6.

     C.   For the purposes hereof, the fair market value of a share of the
Common Stock on any date shall be equal to the closing sale price of a share of
the Common Stock as published by a national securities exchange on which the
shares of the Common Stock are traded on such date or, if there is no sale of
the Common Stock on such date, the average of the bid and asked prices on such
exchange at the close of trading on such date or, if the shares of the Common
Stock are not listed on a national securities exchange on such date, the closing
price in the over the counter market, or if the Common Stock is not traded on a
national securities exchange or the over the counter market, the fair market
value of a share of the Common Stock on such date as shall be determined in good
faith by the Committee in compliance with Section 422(b)(4) of the Code and the
applicable regulations promulgated thereunder.

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8.   Option Term.
     ----------- 

     Participants shall be granted Options for such term as the Committee shall
determine, not in excess of ten years from the date of the granting thereof;
provided, however, that in the case of a Participant who owns more than 10% of
the total combined voting power of the Common Stock at the time an Option which
is an incentive stock option is granted to him, the term with respect to such
Option shall not be in excess of five years from the date of the granting
thereof.

9.   Limitation on Amount of Incentive Stock Options Granted.
     ------------------------------------------------------- 

     The aggregate fair market value (determined at the date of grant) of the
shares of the Common Stock for which any Participant may be granted incentive
stock options which are exercisable for the first time in any calendar year
(whether under the terms of the Plan or any other stock option plan of the
Company) shall not exceed $100,000.  To the extent that any Option which is
intended to be an incentive stock option fails to satisfy the requirements of
this Section, the Option shall be treated as an Option which is not an incentive
stock option.  This Section shall be applied by taking Options into account in
the order in which they are granted.

10.  Exercise of Options.
     ------------------- 

     A.   Options granted to employees of and consultants to the Company or any
Subsidiary shall become exercisable at such times and in such installments as
the Committee shall determine at the time of the grant thereof.  Options
received by directors other than employees of the Company or any Subsidiary
shall become exercisable on the first day of the fiscal year of the Company next
following the year in respect of which such Options are granted.

     B.   Except as hereinbefore otherwise set forth, an Option may be exercised
either in whole or in part at any time or from time to time.

     C.   An Option may be exercised only by a written notice of intent to
exercise such Option with respect to a specified number of shares of the Common
Stock and payment to the Company of the amount of the option price for the
number of shares of the Common Stock so specified; provided, however, that, if
the Committee shall in its sole discretion so determine at the time of the grant
of any Option, all or any portion of such payment may be made in kind by the
delivery of shares of the Common Stock having a fair market value, on the date
of delivery (as determined in the manner set forth in paragraph C of Section 7
hereof), equal to the portion of the option price so paid.

11.  Transferability.
     --------------- 

     No Option shall be assignable or transferable except by will and/or by the
laws of descent and distribution and, during the life of any Participant, each
Option granted to him may be exercised only by him.

12.  Termination of Employment.
     ------------------------- 

     A.   Except as otherwise determined by the Committee, in the event a
Participant leaves the employ or service of the Company and the Subsidiaries for
any reason other than death, retirement or disability (as such term is defined
in section 22(e) of the Code), whether voluntarily or otherwise, each Option
theretofore granted to him which shall not have expired or otherwise been
canceled shall, to the extent it is exercisable on the date of such termination
of employment or service and to the extent it shall not have theretofore been
exercised or become unexercisable, terminate upon the earlier to occur of (i)
the expiration of a period of 90 days after such termination of employment or
service or (ii) the date specified in said Option.

     B.   In the event a Participant's employment or service with the Company
and the Subsidiaries terminates by reason of his death, each Option theretofore
granted to him which shall not have expired or otherwise been canceled shall, to
the extent it is exercisable on the date of such Participant's death and to the
extent it shall not 

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have theretofore been exercised or become unexercisable, terminate upon the
earlier to occur of (i) the expiration of a period of one year after such
Participant's death or (ii) the date specified in said Option.

     C.   In the event a Participant's employment or service with the Company
and the Subsidiaries terminates by reason of his retirement, whether voluntarily
or as may be required by any pension plan, or by reason of his disability (as
such term is defined in section 22(e) of the Code), each Option theretofore
granted to him which shall not have expired or otherwise been canceled shall
become immediately exercisable in full and shall, to the extent it shall not
have theretofore been exercised or become unexercisable, terminate upon the
earlier to occur of (i) the expiration of 90 days after the date of such
Participant's retirement or disability or (ii) the date specified in said
Option.

     D.   The Committee or the Board may in its discretion extend the period
during which an Option held by any employee of or consultant to the Company or
any Subsidiary may be exercised to such period, not to exceed three years
following the termination of a Participant's employment or service with the
Company or any of the Subsidiaries, as the Committee or the Board may determine
to be appropriate in any particular instance.

13.  Adjustment of Number of Shares.
     ------------------------------ 

     A.   In the event that a dividend shall be declared upon the Common Stock
payable in shares of the Common Stock, the number of shares of the Common Stock
then subject to any Option and the number of shares of the Common Stock reserved
for issuance in accordance with the provisions of the Plan but not yet covered
by an Option shall be adjusted by adding to each share the number of shares
which would be distributable thereon if such share had been outstanding on the
date fixed for determining the shareholders entitled to receive such stock
dividend.  In the event that the outstanding shares of the Common Stock shall be
changed into or exchanged for a different number or kind of shares of stock or
other securities of the Company or of another corporation, whether through
reorganization, recapitalization, stock split-up, combination of shares, sale of
assets, merger or consolidation, then, there shall be substituted for each share
of the Common Stock then subject to any Option and for each share of the Common
Stock reserved for issuance in accordance with the provisions of the Plan but
not yet covered by an Option, the number and kind of shares of stock or other
securities into which each outstanding share of the Common Stock shall be so
changed or for which each such share shall be exchanged; provided, however,
that, in the event of a merger or consolidation in which the Company is not the
surviving corporation or of a sale by the Company of all or substantially all of
its assets to a corporation not controlled by the Company (within the meaning of
section 1563(a)(1) of the Code) immediately prior to such transaction, the Board
determines, in its discretion, that such change or exchange cannot be effected
or would be inappropriate, then, each Option theretofore granted to a
Participant which shall not have expired or otherwise been canceled shall become
immediately exercisable in full and shall terminate upon the later to occur of
(i) the expiration of 30 days following notice to the Participant by the Company
of such merger, consolidation or sale, or (ii) the date of such merger,
consolidation or sale.

     B.   In the event that there shall be any change, other than as specified
in this Section 13, in the number or kind of outstanding shares of the Common
Stock, or of any stock or other securities into which the Common Stock shall
have been changed, or for which it shall have been exchanged, then, if the
Committee shall, in its sole discretion, determine that such change equitably
requires an adjustment in the number or kind of shares then subject to any
Option and the number or kind of shares reserved for issuance in accordance with
the provisions of the Plan but not yet covered by an Option, such adjustment
shall be made by the Committee and shall be effective and binding for all
purposes of the Plan and of each stock option agreement entered into in
accordance with the provisions of the Plan.

     C.   In the case of any substitution or adjustment in accordance with the
provisions of this Section 13, the option price in each stock option agreement
for each share covered thereby prior to such substitution or adjustment shall be
the option price for all shares of stock or other securities which shall have
been substituted for such share or to which such share shall have been adjusted
in accordance with the provisions of this Section 13.  No adjustment or
substitution provided for in this Section 13 shall require the Company to sell a
fractional share under any stock option agreement.

14.  Purchase for Investment and Waivers.
     ----------------------------------- 

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     A.   Unless the shares to be issued upon the exercise of an Option by a
Participant shall be registered prior to the issuance thereof under the
Securities Act of 1933, as amended, such Participant shall, as a condition of
the Company's obligation to issue such shares, be required to give a
representation in writing that he is acquiring such shares for his own account
as an investment and not with a view to, or for sale in connection with, the
distribution of any thereof.

     B.   In the event of the death of a Participant, an additional condition of
exercising any Option shall be the delivery to the Company of such tax waivers
and other documents as the Committee shall determine.

     C.   Each Participant shall be required, as a condition of exercising any
Option which is not an incentive stock option, to make such arrangements with
the Company with respect to withholding as the Committee shall determine.

15.  Amendment of Plan.
     ----------------- 

     The Board may at any time make such modifications of the Plan as it shall
deem advisable; provided, however, that (i) the provisions hereof relating to
the receipt of Options by directors of the Company who are not employees of the
Company or any Subsidiary, the exercise price and terms and conditions of the
exercise thereof may not be amended more than once in any period of six months,
except as may be required to comply with changes in the Code or the Employee
Retirement Income Security Act of 1974, as amended, and (ii) the Board may not
without further approval of shareholders representing a majority of the voting
power present in person or by proxy at any special or annual meeting of
shareholders increase the number of shares of the Common Stock as to which
Options may be granted under the Plan (as adjusted in accordance with the
provisions of Section 13 hereof), or change the class of persons eligible to
participate in the Plan or change the manner of determining the option prices
which would result in a decrease in the option price, or extend the period
during which an Option may be granted or exercised.  Except as otherwise
provided in Section 16 hereof, no termination or amendment of the Plan may,
without the consent of the Participant to whom any Option shall theretofore have
been granted, adversely affect the rights of such Participant under such Option.

16.  Expiration and Termination of the Plan.
     -------------------------------------- 

     The Plan shall terminate on October 31, 2006 or at such earlier time as the
Board may determine.  Options may be granted under the Plan at any time and from
time to time prior to its termination.  Any Option outstanding under the Plan at
the time of the termination of the Plan shall remain in effect until such Option
shall have been exercised or shall have expired in accordance with its terms.

17.  Options Granted in Connection with Acquisitions.
     ----------------------------------------------- 

     In the event that the Committee determines that, in connection with the
acquisition by the Company of another corporation which shall become a
Subsidiary of the Company (such corporation being hereinafter referred to as an
"Acquired Subsidiary"), Options may be granted hereunder to key employees of an
Acquired Subsidiary in exchange for then outstanding options to purchase
securities of the Acquired Subsidiary, such Options may be granted at such
option prices, may be exercisable immediately or at any time or times either in
whole or in part, may be granted without the requirement that the Participant
enter into an agreement with the Company that he will remain in the employ or
service of the Company or a Subsidiary for any required period of time and may
contain such other provisions not inconsistent with the Plan, or the requirement
set forth in Section 15 hereof that certain amendments to the Plan must be
approved by the shareholders of the Company, as the Committee, in its
discretion, shall deem appropriate at the time of the granting of such Options.

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