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                                                                   EXHIBIT 10.15

                 INTEGRATED BUSINESS SYSTEMS AND SERVICES, INC.

                       NONQUALIFIED STOCK OPTION AGREEMENT

         This Agreement, dated as of May 30, 2000, implements the grant of a
nonqualified stock option pursuant to action of the Board of Directors (the
"Board") of INTEGRATED BUSINESS SYSTEMS AND SERVICES, INC. (the "Company") to
WILLIAM SPENCER MCMASTER (the "Optionee") subject to the terms and conditions
set forth below.

         The Company desires to afford the Optionee the opportunity to acquire
shares of the Company's common stock, no par value per share ("Stock"), so the
Optionee has a proprietary interest in the Company, and the Optionee desires the
opportunity to acquire shares of Stock. For purposes of this Agreement, in the
event the outstanding shares of Stock are hereafter changed into or exchanged
for shares of a different stock or securities of the Company or some other
entity, the term "Stock" shall also refer to such other stock or securities.
Accordingly, the Company and the Optionee agree as follows:

1. Grant of Option and Purchase Price. The Company, pursuant to action of the
Board, hereby grants to the Optionee an Option to purchase a total of fifty
thousand, two (50,002) shares of Stock at an exercise price per share of Six and
No/100ths ($6.00) Dollars (the "Exercise Price"), such number of shares and
Exercise Price being subject to adjustment as provided herein.

2. Expiration of the Option. This Option shall expire ("Expiration Date") on the
earlier of (i) ten (10) years from the date hereof or (ii) the date this Option
is fully exercised.

3. Vesting, Exercise and Conversion of Option.

         3.1. Option Vesting. This Option shall vest and become exercisable
and/or convertible as follows: (i) eight thousand, three hundred thirty-four
(8,334) shares on each of November 30, 2000, May 31, 2001, and May 31, 2002, and
(ii) twenty-five thousand (25,000) shares on November 30, 2001. Notwithstanding
any provision in this Agreement to the contrary, all unvested options granted
pursuant to this Agreement shall immediately vest and become fully exercisable
and/or convertible and remain exercisable and/or convertible throughout their
entire term (a) upon termination of Optionee's employment pursuant to Section
5(b) of that certain Employment Agreement dated as of May 30, 2000 by and
between the Company and the Optionee, and (b) upon the occurrence of a "Change
in Control" of the Company as defined herein.

For purposes of this Agreement, the term "Change in Control" shall mean that any
one of the following events shall have occurred: (i) a person, partnership,
joint venture, corporation or other entity, or two or more of any of the
foregoing acting as a group (or a "person" within the meaning of Section
13(d)(3) of the Securities Exchange Act of 1934, as amended (the "1934 Act"),
other than the Company, a majority-owned subsidiary of the Company, an employee
benefit plan (or related trust) of the Company or such subsidiary, (A) directly
or indirectly become(s) after the effective date

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of grant of the stock options hereunder the "beneficial owner" (as defined in
Rule 13(d)(3) under the 1934 Act) of 15% or more of the then outstanding voting
securities of the Company, or (B) makes a tender offer for 15% or more of the
outstanding voting securities of the Company; or (ii) individuals who constitute
a majority of the Board at the effective date hereof, or individuals elected or
nominated directly or indirectly by at least a majority of such current
directors, no longer constitute a majority of the members of the Board; or (iii)
the Company enters into (A) a plan of complete liquidation of the Company; or
(B) an agreement for the sale or disposition of all or substantially all of the
Company's assets (other than to a subsidiary of the Company); or (C) a merger,
consolidation, or reorganization of the Company with or involving any other
corporation, other than a merger, consolidation, or reorganization that would
result in the voting securities of the Company outstanding immediately prior
thereto continuing to represent (either by remaining outstanding or by being
converted into voting securities of the surviving entity) at least seventy-five
percent (75%) of the combined voting power of the voting securities of the
Company (or such surviving entity) outstanding immediately after such merger,
consolidation or reorganization. Vested portions of this Option may be exercised
at any time, in whole or in part, before the Expiration Date.

         3.2. Option Exercise.

         (a) This Option may be exercised by (i) delivery to the Company at its
principal office a written notice of exercise with respect to a specified number
of shares of Stock and (ii) payment to the Company at that office of the full
amount of the Exercise Price for such number of shares in accordance with
Section 3.2 (b). If requested by the Optionee, this Option may be exercised with
the involvement of a stockbroker in accordance with the federal margin rules set
forth in Regulation T (in which case the certificates representing the
underlying shares will be delivered by the Company directly to the stockbroker).

         (b) The Exercise Price is to be paid in full in cash upon the exercise
of this Option and the Company shall not be required to deliver certificates for
the shares purchased until such payment has been made; provided, however, that
(i) in lieu of cash, all or any portion of the Exercise Price may be paid by
tendering to the Company shares of Stock duly endorsed for transfer and owned by
the Optionee, or by authorization to the Company to withhold shares of Stock
otherwise issuable upon exercise of the Option, in each case to be credited
against the Exercise Price at the Fair Market Value (as defined herein) of such
shares on the date of exercise (however, no fractional shares may be so
transferred, and the Company shall not be obligated to make any cash payments in
consideration of any excess of the aggregate Fair Market Value of shares
transferred over the aggregate Exercise Price); and (ii) in lieu of cash or
shares of Stock, all or a portion of the Exercise Price may be paid by the
Optionee's execution of a recourse note equal to the Exercise Price or relevant
portion thereof. The Option shall be deemed exercised and the shares of Stock
purchased thereby shall be deemed issued as of the date such payment is received
by the Company.

         3.3 Conversion of Option. In lieu of the exercise of this all or any
portion of this Option pursuant to Section 3.2 above, the Optionee may convert
all or a portion of this Option by the surrender of this Option Agreement and
delivery of the Notice of Conversion form attached hereto,

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duly executed, at the principal executive offices of the Company into shares of
Stock as provided in this Section 3.3. Upon exercise of this conversion right,
the Optionee shall be entitled to receive, and shall promptly (but in no event
more than 10 days after such delivery) receive, that number of shares of Stock
equal to the quotient obtained by dividing [(A-B)(X)] by (A), where:

A        =        the current Fair Market Value (as defined herein) of one
                  share of Stock on the date of conversion of this Option.

B        =        the Exercise Price for one share of Stock under this Option.

X        =        the number of shares of Stock with respect to which this
                  Option is being converted.

         If the above calculation results in a negative number, then no shares
of Stock shall be issued or issuable upon conversion of this Option.

         By way of illustration, if the Exercise Price is $10.00 per share of
Stock, the current Fair Market Value is $20.00 per share of Stock, and the
Option is being converted with respect to 100,000 shares of Stock, then 50,000
shares of Stock would be issued on conversion [($20.00 - $10.00) x 100,000
divided by $20.00 = 50,000] and the number of shares of Stock issuable upon
exercise of the Option would be reduced by 100,000.

         As used in this Agreement, the term "Fair Market Value" shall mean on
any date (i) where the Stock is listed for trading on a stock exchange or over
the counter market, the closing price of the Stock on the stock exchange or over
the counter market which is the principal trading market for the Stock, or (ii)
where the Stock is not listed for trading on a stock exchange or over the
counter market, the value which is determined by the Board to be the fair value
of the Stock, taking into consideration all factors that the Board deems
appropriate, including, without limitation, recent sale and offer prices of the
Stock in private transactions negotiated at arm's length.

4. Transferability of Option. This Option and all rights hereunder may not be
sold, transferred, assigned, pledged or hypothecated, except in accordance with
the prior written consent of the Company. This Option is exchangeable, without
expense, at the option of the holder, upon presentation and surrender hereof at
the principal executive offices of the Company, for other options of different
denominations entitling the holder thereof to purchase in the aggregate the same
number of shares of Common Stock purchasable hereunder. Except as limited
herein, this Option and all rights hereunder are transferable by the holder
hereof in person or by duly authorized attorney on the books of the Company upon
surrender of this Option at the principal executive offices of the Company,
together with the Assignment form attached hereto duly executed. Absent any such
transfer, the Company may deem and treat the registered holder of this Option at
any time as the absolute owner hereof for all purposes and shall not be affected
by any notice to the contrary.

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5. Antidilution.

         5.1 In case at any time after the date of this Agreement (i) the
Company issues any shares of its capital stock in a reclassification of the
outstanding Stock (including any such reclassification in connection with a
consolidation or merger in which the Company is the continuing corporation), or
(ii) the outstanding shares of Stock are changed into or exchanged for a
different number or kind of shares or other securities of the Company or other
entity by reason of merger, consolidation, reorganization, recapitalization,
reclassification, combination or exchange of shares, or forward or reverse stock
split, stock dividend, or similar event or (iii) the Company makes any other
distribution in kind on shares of its outstanding Stock, or (iv) any spin-off,
spin-out or other distribution of assets of the Company materially affects the
price of the Company 's stock, then the Exercise Price and the number of shares
of Stock purchasable hereunder in effect at the time of the record date for such
dividend or of the effective date of such stock split, subdivision, combination,
reclassification, distribution, merger, share exchange, consolidation,
reorganization, recapitalization, spin-off or spin- out shall be proportionately
adjusted so that the holder of the Option exercised after such time shall be
entitled to receive the aggregate number and kind of shares of capital stock
which, if such Option had been exercised immediately prior to such date, such
holder would have owned upon such exercise and been entitled to receive by
virtue of such event. Such adjustment shall be made successively whenever any
event listed above shall occur.

         5.2 Notwithstanding an adjustment in the Exercise Price or in the
number of shares of Stock purchasable upon the exercise of the Option pursuant
to Section 5.1, the Company shall not be required to issue fractions of shares
of Stock upon exercise of the Option or to distribute certificates which
evidence fractional shares. In lieu of fractional shares, there shall be paid to
the holder of the Option at the time such Option is exercised or converted, as
herein provided, an amount in cash equal to the same fraction of the current
Fair Market Value of a share of Stock.

         6. Covenants of Company. The Company covenants and agrees that all
shares of Stock and, if applicable, other securities that may be issued upon the
exercise of the rights represented by this Option will, upon issuance, be fully
paid and nonassessable and free from all taxes, liens and charges with respect
to the issue thereof (other than taxes in respect of any transfer to a person
other than the holder of this Option occurring contemporaneously with such
issue). The Company further covenants and agrees that during the period within
which the rights represented by this Option may be exercised, the Company will
at all times have authorized and reserved a sufficient number of shares of Stock
and, if applicable, other securities to provide for the exercise in full of the
rights represented by this Option.

         7. Successors and Assigns. This Option and the rights evidenced hereby
shall inure to the benefit of and be binding upon the successors and assigns of
the Company and the holder hereof. Specifically, all obligations of the Company
under this Agreement shall be binding on any successor to the Company, whether
the existence of such successor is the result of a direct or indirect purchase
of all or substantially all of the business and/or assets of the Company, or a
merger, consolidation or otherwise. Specifically, in case of any capital
reorganization of the Company, or of any

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reclassification of any shares of Stock (other than a change as a result of
subdivision or combination), or in case of the consolidation of the Company with
or the merger of the Company with any other corporation or entity (other than a
consolidation or merger in which (i) the Company is the continuing corporation
and (ii) the holders of the shares of Stock immediately prior to such merger or
consolidation continue as holders of at least 75% of the outstanding shares of
Stock after such merger or consolidation) or of the sale of the properties and
assets of the Company as, or substantially as, an entirety to any other
corporation or other entity, any unexercised portion of this Option outstanding
immediately prior to such event shall after such reorganization,
reclassification, consolidation, merger or sale be exercisable, upon the terms
and conditions specified herein for or with respect to the number of shares of
Stock or other securities or property to which a holder of this Option, upon
exercise of such Option immediately prior to such reorganization,
reclassification, consolidation, merger or sale, would have been entitled to
receive in connection with such reorganization, reclassification, consolidation,
merger or sale; and in any such case, if necessary, the provisions set forth in
this Section with respect to the rights and interests thereafter of the holder
of this Option shall be appropriately adjusted so as to be applicable, as nearly
as may reasonably be, to any shares of stock or other securities or property
thereafter deliverable on the exercise of this Option.

8. Entire Agreement. This Agreement constitutes the entire Agreement between the
Optionee and the Company with respect to the Option granted hereunder.

9. Applicable Law. The validity, interpretation, enforcement and performance of
this Agreement shall be governed by the laws of the State of South Carolina.

                                 INTEGRATED BUSINESS SYSTEMS AND SERVICES, INC.

                                 By: /s/ HARRY P. LANGLEY
                                     ------------------------------------------

                                     Its: President and Chief Executive Officer
                                          -------------------------------------


                                 OPTIONEE

                                 /s/ WILLIAM S. MCMASTER
                                 ----------------------------------------------
                                 William Spencer McMaster

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                               NOTICE OF EXERCISE

         The undersigned registered holder or assignee of such registered holder
of the within Option, hereby elects to purchase ________ shares of Common Stock
of the Company, which the undersigned is entitled to purchase under the terms of
the within Option, and tenders herewith payment therefor in full. Such shares
shall be issued in the name of the undersigned or as otherwise specified below:

                               ------------------
                                     (Name)

                               ------------------
                                    (Address)

         If the shares issuable upon exercise do not constitute all shares
issuable as provided in the within Option, a new option agreement of like tenor
for the number of shares of Common Stock of the Company not being purchased
hereunder shall be issued in the name of the undersigned.


Dated:               , 20         By:
      ---------------    -----       -------------------------------------------
                                                     (Signature)

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                              NOTICE OF CONVERSION

         The undersigned registered holder or assignee of such registered holder
of the within Option, pursuant to Section 3.3 of the within Option, instructs
and agrees that this Option (or portion therof) be converted into the number of
shares of Common Stock of the Company as determined pursuant to Section 3.3 of
the within Option, and that the number of shares of Stock issuable pursuant to
this Option be reduced by the number of shares of Stock with respect to which
this Option is being converted. Shares of Stock issued upon conversion of this
Option shall be issued in the name of the undersigned or as specified below:

                               ------------------
                                     (Name)

                               ------------------
                                    (Address)

         If this Option is not converted in full, a new stock option agreement
of like tenor for the number of shares of Stock as to which the within Option
may be exercised following such conversion shall be issued in the name of the
undersigned.


Dated:               , 20         By:
      ---------------    -----       -------------------------------------------
                                                     (Signature)

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                                   ASSIGNMENT

         FOR VALUE RECEIVED ____________________________ hereby sells, assigns,
and transfers unto _______________, whose address is __________________________
____________________, the right to purchase _____________ shares of Stock
evidenced by the within Option, and does hereby irrevocably constitute and
appoint ___________________ Attorney to transfer such right on the books of the
Company, with full power of substitution.

Dated:                         , 20
      -------------------------    -------



                                           -------------------------------------
                                                     (Signature)

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