<PAGE>

                                  EXHIBIT 99.1

                             ZOOM TELEPHONICS, INC.
                       1998 EMPLOYEE EQUITY INCENTIVE PLAN
                           AS AMENDED ON JUNE 16, 2000

Section 1.  NAME AND PURPOSE

         This plan shall be known as the Zoom Telephonics, Inc. 1998 Employee
Equity Incentive Plan, as amended (the "Plan"). The purpose of the Plan is to
attract and retain employees and provide an incentive for them to assist Zoom
Telephonics, Inc. (the "Company") to achieve long-range performance goals, and
to enable them to participate in the long-term growth of the Company.

Section 2.  DEFINITIONS

(a) "Award" means any Option awarded under the Plan.

(b) "Board" means the Board of Directors of the Company.

(c) "Code" means the Internal Revenue Code of 1986, as amended from time to
     time.

(d) "Committee" means the Stock Option Committee of the Board, or such other
    committee of not less than three members of the Board appointed by the
    Board to administer the Plan.

(e) "Common Stock" or "Stock" means the Common Stock, no par value, of the
    Company.

(f) "Company" means Zoom Telephonics, Inc. and any business entity in which
    Zoom Telephonics, Inc. owns directly or indirectly 50% or more of the
    total combined voting power or has a significant financial interest as
    determined by the Committee.

(g) "Designated Beneficiary" means the beneficiary designated by a
    Participant, in a manner determined by the Board, to receive amounts due
    or exercise rights of the Participant in the event of the Participant's
    death. In the absence of an effective designation by a Participant,
    Designated Beneficiary shall mean the Participant's estate.

(h) "Fair Market Value" means, with respect to Common Stock or any other
    property, the fair market value of such property as determined by the
    Board in good faith or in the manner established by the Board from time to
    time.

(i) "Nonqualified Stock Option" means an option to purchase shares of Common
    Stock, awarded to a Participant under Section 6, which is not intended to
    comply as an incentive stock option under Section 422 of the Code or any
    successor provision.

(j) "Option" means a Nonqualified Stock Option.

(k) "Officer" means any individual who is a designated corporate officer of
    the Company or is deemed an officer of the Company under Rule 16b-3
    promulgated under the Securities Exchange Act of 1934, as amended (or any
    successor or supplementary law, rule or regulation), or is deemed an
    officer under Rule 4310 of the Marketplace Rules of The Nasdaq Stock
    Market, Inc (or any successor or supplementary law, rule or regulation).

(l) "Participant" means a person eligible pursuant to Section 4 hereof and
    selected by the Board to receive an Award under the Plan.

<PAGE>

Section 3.  ADMINISTRATION

         The Plan shall be administered by the Committee. The Board shall have
authority to adopt, alter and repeal such administrative rules, guidelines and
practices governing the operation of the Plan as it shall from time to time
consider advisable, and to interpret the provisions of the Plan. The Board's
decisions shall be final and binding. To the extent permitted by applicable law,
the Board may delegate to the Committee the power to make Awards to Participants
and all determinations under the Plan with respect thereto.

Section 4.  ELIGIBILITY

         All employees of the Company, other than Officers and directors of the
Company, are eligible to be Participants in the Plan.

Section 5.  STOCK AVAILABLE FOR AWARDS

(a)  Subject to adjustment under subsection (b), Awards may be made under the
     Plan of Options to acquire not in excess of 950,000 shares of Common Stock.
     If any Award in respect of shares of Common Stock expires or is terminated
     unexercised or is forfeited for any reason or settled in a manner that
     results in fewer shares outstanding than were initially awarded, including
     without limitation the surrender of shares in payment for the Award or any
     tax obligation thereon, the shares subject to such Award or so surrendered,
     as the case may be, to the extent of such expiration, termination,
     forfeiture or decrease, shall again be available for award under the Plan.
     Common Stock issued through the assumption or substitution of outstanding
     grants from an acquired Company shall not reduce the shares available for
     Awards under the Plan. Shares of Common Stock issued under the Plan may
     consist in whole or in part of authorized but unissued shares or treasury
     shares.

(b)  In the event that the Board determines that any stock dividend,
     extraordinary cash dividend, creation of a class of equity securities,
     recapitalization, reorganization, merger, consolidation, split-up,
     spin-off, combination, exchange of shares, warrants or rights offering to
     purchase Common Stock at a price substantially below fair market value, or
     other similar transaction affects the Common Stock such that an adjustment
     is required in order to preserve the benefits or potential benefits
     intended to be made available under the Plan, then the Board, shall
     equitably adjust any or all of (i) the number and kind of shares in respect
     of which Awards may be made under the Plan, (ii) the number and kind of
     shares subject to outstanding Awards, and (iii) the award, exercise or
     conversion price with respect to any of the foregoing, and if considered
     appropriate, the Board may make provision for a cash payment with respect
     to an outstanding Award, provided that the number of shares subject to any
     Award shall always be a whole number.

Section 6.  STOCK OPTIONS

(a)  Subject to the provisions of the Plan, the Board may award Nonqualified
     Stock Options and determine the number of shares to be covered by each
     Option, the Option Price therefor and the conditions and limitations
     applicable to the exercise of the Option.

(b) The Board shall establish the Option Price at the time each Option is
    awarded.

<PAGE>

(c)  Each Option shall be exercisable at such times and subject to such terms
     and conditions as the Board may specify in the applicable Award or
     thereafter. The Board may impose such conditions with respect to the
     exercise of Options, including conditions relating to applicable federal or
     state securities laws, as it considers necessary or advisable.

(d)  No shares shall be delivered pursuant to any exercise of an Option until
     payment in full of the Option Price therefor is received by the Company.
     Such payment may be made in whole or in part in cash or, to the extent
     permitted by the Board at or after the award of the Option, by delivery of
     a note or shares of Common Stock owned by the optionholder, including
     restricted stock, valued at their Fair Market Value on the date of
     delivery, by the reduction of the shares of Common Stock that the
     optionholder would be entitled to receive upon exercise of the Option, such
     shares to be valued at their Fair Market Value on the date of exercise,
     less their Option Price (a so-called "cashless exercise"), or such other
     lawful consideration as the Board may determine. In addition, an
     optionholder may engage in a successive exchange (or series of exchanges)
     in which the shares of Common Stock that such optionholder is entitled to
     receive upon the exercise of an Option may be simultaneously utilized as
     payment for the exercise of an additional Option or Options.

(e)  The Board may provide for the automatic award of an Option upon the
     delivery of shares to the Company in payment of an Option for up to the
     number of shares so delivered.

Section 7.  GENERAL PROVISIONS APPLICABLE TO AWARDS

(a)  DOCUMENTATION. Each Award under the Plan shall be evidenced by a writing
     delivered to the Participant specifying the terms and conditions thereof
     and containing such other terms and conditions not inconsistent with the
     provisions of the Plan as the Board considers necessary or advisable to
     achieve the purposes of the Plan or comply with applicable tax and
     regulatory laws and accounting principles.

(b)  BOARD DISCRETION. The terms of each Award need not be identical, and the
     Board need not treat Participants uniformly. Except as otherwise provided
     by the Plan or a particular Award, any determination with respect to an
     Award may be made by the Board at the time of award or at any time
     thereafter. Without limiting the foregoing, an Award may be made by the
     Board, in its discretion, to any 401(k), savings, pension, profit sharing
     or other similar plan of the Company in lieu of or in addition to any cash
     or other property contributed or to be contributed to such plan.

(c)  SETTLEMENT. The Board shall determine whether Awards are settled in whole
     or in part in cash, Common Stock, other securities of the Company, Awards
     or other property. The Board may permit a Participant to defer all or any
     portion of a payment under the Plan, including the crediting of interest on
     deferred amounts denominated in cash and dividend equivalents on amounts
     denominated in Common Stock.

(d)  TERMINATION OF EMPLOYMENT. The Board shall determine the effect on an Award
     of the disability, death, retirement or other termination of employment of
     a Participant and the extent to which, and the period during which, the
     Participant's legal representative, guardian or Designated Beneficiary may
     receive payment of an Award or exercise rights thereunder.

(e)  CHANGE IN CONTROL. In order to preserve a Participant's rights under an
     Award in the event of a change in control of the Company, the Board in its
     discretion may, at the time an Award is made or at any time thereafter,
     take one or more of the following actions: (i) provide for the acceleration
     of any time period relating to the exercise of the Award, (ii) provide for
     the purchase of the Award upon the Participant's request for an amount of
     cash or other property that could have been received upon the exercise of
     the Award had the Award been currently exercisable, (iii) adjust the terms
     of the Award in a manner determined by the Board to reflect the change in
     control, (iv) cause the Award to be assumed, or new rights substituted
     therefor, by another entity, or (v) make such other provision as the Board
     may consider equitable and in the best interests of the Company.

<PAGE>

(f)  WITHHOLDING. The Participant shall pay to the Company, or make provision
     satisfactory to the Board for payment of, any taxes required by law to be
     withheld in respect of Awards under the Plan no later than the date of the
     event creating the tax liability. In the Board's discretion, such tax
     obligations may be paid in whole or in part in shares of Common Stock,
     including shares retained from the Award creating the tax obligation,
     valued at their Fair Market Value on the date of delivery. The Company and
     its affiliates may, to the extent permitted by law, deduct any such tax
     obligations from any payment of any kind otherwise due to the Participant.

(g)  AMENDMENT OF AWARD. The Board may amend, modify or terminate any
     outstanding Award, including substituting therefor another Award of the
     same or a different type, changing the date of exercise, provided that the
     Participant's consent to such action shall be required unless the Board
     determines that the action, taking into account any related action, would
     not materially and adversely affect the Participant.

Section 8.  MISCELLANEOUS

(a)  NO RIGHT TO EMPLOYMENT. No person shall have any claim or right to be
     granted an Award, and the grant of an Award shall not be construed as
     giving a Participant the right to continued employment. The Company
     expressly reserves the right at any time to dismiss a Participant free from
     any liability or claim under the Plan, except as expressly provided in the
     applicable Award.

(b)  NO RIGHTS AS SHAREHOLDER. Subject to the provisions of the applicable
     Award, no Participant or Designated Beneficiary shall have any rights as a
     shareholder with respect to any shares of Common Stock to be distributed
     under the Plan until he or she becomes the holder thereof.

(c)  GOVERNING LAW. The provisions of the Plan shall be governed by and
     interpreted in accordance with the laws of the Commonwealth of
     Massachusetts.

(d)  INDEMNITY. Neither the Board nor the Committee, nor any members of either,
     nor any employees of the Company or any parent, subsidiary, or other
     affiliate, shall be liable for any act, omission, interpretation,
     construction or determination made in good faith in connection with their
     responsibilities with respect to this Plan, and the Company hereby agrees
     to indemnify the members of the Board, the members of the Committee, and
     the employees of the Company and its parent or subsidiaries in respect of
     any claim, loss, damage, or expense (including reasonable counsel fees)
     arising from any such act, omission, interpretation, construction or
     determination to the full extent permitted by law.