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                                                                    EXHIBIT 10.5


                    [PETROCHEMNET HOLDINGS, INC. LETTERHEAD]



CONFIDENTIAL
September 6, 1999


Mr. Lawrance Wiley McAfee
11414 Dunbeath Drive
Houston, Texas 77024


Via Fax: 713-463-9688

Dear Larry:

I am pleased to offer you an exciting and rewarding employment opportunity with
PetroChemNet Holdings, Inc., a Delaware Corporation ("the Company"). We believe
that you will be a vital contributor to the continued growth and success of the
Company.

As we discussed, your position with the Company will be salaried (non-hourly),
with the title of Senior Vice President and Chief Financial Officer, reporting
to me. Your position will be located in Houston.

The following terms outline some essential points regarding this offer:

SERVICES: As Chief Financial Officer, you shall have overall responsibility for
management of the Company's financial affairs including accounting, corporate
finance, treasury, cash management, risk management, investor relations,
commercial and investment banking. Of course, travel may be required depending
upon the location of our investors and financial institutions.

COMPENSATION: The Company is pleased to provide you with the following initial
compensation package:

     BASE SALARY: A monthly salary of $16,667.00, payable in accordance with the
          Company's regular payroll interval, which is currently bi-weekly.

     BONUS PROGRAM: In addition to your salary set forth above, you shall be
          eligible to receive a performance based target cash bonus of 50% of
          your salary, with an upside of 100% of base and a downside of 0% of
          base, depending upon your performance.

     IPO BONUS PROGRAM: In addition, you will be eligible to receive a target
          bonus of up to 15% of the total bonus pool provided under the
          Management Incentive Plan in the




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          event the company successfully completes and IPO or sale, subject to
          your performance.

STOCK OPTIONS PLAN:


     STOCK OPTIONS: In partial consideration for your agreement to sign the
employee confidentiality, non-disclosure, assignment, and non-solicitation
agreement prior to commencing employment, you will receive options to purchase
106,526 of the Company's shares of the Company common stock at a price of $1.336
per share under the terms and conditions set forth in the Incentive Stock Option
and Stock Repurchase Agreement that is being executed simultaneously with this
Agreement and is hereby incorporated by reference into this letter, subject to
the Incentive Stock Option and Stock Repurchase Agreement which is subject to
approval by the Company's Board of Directors. The Company makes no
representations regarding the potential value of these options because as a
start-up company it is difficult to provide any estimates with regard to future
value. The options will have a four year vesting schedule with 25% vesting after
one year of service and each month thereafter l/36th of the remaining options
will vest. In the event of a change of control, if you do not receive the
position of CFO of the surviving parent company, you will vest in one-half of
the remaining unvested options.


The Stock Option Plan and the granting of any shares and exercise of any options
for shares and the obligations of the Company to sell and deliver shares and
options shall be subject to all applicable laws, rules, and regulations and to
such approvals by any governmental agencies as may be required. The Company does
not represent that such approvals have been or will be received. Any stock
options granted under the plan will be subject to the terms of the plan, a copy
of which will be provided upon request.

Also, in order to comply with applicable securities laws, the Company shall have
the right to:

     a.   require any shareholder/option holder to execute, as a condition of
     the receipt of shares or exercise of an option, a letter evidencing the
     shareholder/option holder's intent to acquire the shares for investment and
     not with a view to the resale or distribution thereof;

     b.   place appropriate legends upon the certificates for the shares; and

     c.   take such other acts as it deems necessary in order to cause the
     issuance of shares and optioned shares to comply with applicable provisions
     of state and federal securities laws.

In furtherance of these requirements, and without limitation, no shares shall be
saleable or option shall be exercisable unless such shares and options shall be
registered under appropriate federal and state securities laws, or shall be
exempt therefrom, in the opinion of the Company upon advice of counsel to the
Company. Each share grant and option agreement shall contain adequate provisions
to assure that there will be no violation of such laws. This provision shall in
no way obligate the Company to undertake registration of shares or options
hereunder. Issue, transfer, or delivery of certificates for shares or options
may be delayed or terminated, at the discretion of the Company,


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until the Company is satisfied that the applicable requirements of the federal
and state securities laws have been met or compliance can easily occur without
the Company incurring material expense.


ADDITIONAL OPTIONS: You have requested an anti-dilution provision which would
restore your options to the original level upon subsequent financings. As you
know, this would require approval from unknown future investors and financial
institutions as well as the Board of Directors in the future. I agree to
recommend you for future option grants depending upon your performance in the
future but can not guarantee the level and timing of the actual grants since
this will depend upon your performance, future financings, and Board approval. I
intend to reward high performance through the issuance of future options grants.

PURCHASE OF COMPANY STOCK: You have expressed interest in potentially purchasing
approximately $100,000 of company stock in the next round of financing. We have
not finalized the plans which would enable this to occur. I agree to support
your efforts to purchase stock and to develop a broader based opportunity for
accredited management employees to purchase stock.

EMPLOYEE BENEFITS AND ORIENTATION: As an employee, you will be eligible to
participate in the Company's employee benefits plans as in effect from time to
time, including medical, dental, 401(k) or equivalent retirement plan, and sick
time. You also will receive four (4) weeks of vacation the first year that will
accrue at the rate of 1.67 days per month and then will be eligible for four (4)
weeks vacation for each year thereafter. On or shortly after your start date, a
new employee orientation will be scheduled to acquaint you with the Company's
policies and procedures, as well as Company-provided benefits as they may exist
from time to time. At that time, any required employee benefit documents,
including payroll information, will be provided for your completion. The Company
retains the right to alter, amend, substitute, or terminate any benefit plans
now in place or offered in the future. The Company is evaluating the
implementation of various benefits programs and anticipates implementing a range
of benefits programs consistent with the company's size.

IMPORTANT CONTINGENCIES TO OFFER:

This employment offer is also conditioned upon the following:

     A) IMMIGRATION STATUS: Pursuant to the Immigration Reform Act of 1986, you
     must present acceptable proof of identity and the legal right to work in
     the United States on your first day of employment at the Company.


     B) CONFIDENTIALITY, NON-DISCLOSURE, ASSIGNMENT, AND NON-SOLICITATION
     AGREEMENT: You agree that all inventions and work product arising from
     your employment with the Company will be the exclusive property of the
     Company. You will be required to complete, sign, and return the enclosed
     employee confidentiality, non-disclosure, assignment, and non-solicitation
     agreement prior to commencing employment.


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     C) OTHER: You represent that your employment with the Company will not
     require you to violate any obligation to or confidence of any other person
     or entity.

COMPANY POLICIES AND PROCEDURES: You agree to be bound by all Company employee
policies and procedures in effect from time to time. The Company may modify such
policies and procedures.

EMPLOYMENT AT WILL: Your employment relationship will be "at will," despite
anything to the contrary in this letter or any other communication from the
Company (including employee manuals). This means that you have the right to
terminate your employment with the Company at any time, and that the Company has
the right to terminate your employment at any time with or without cause or
reason. Nothing in this offer letter is a contract of employment for any
definite period of time or a guarantee for a continued specific job or
responsibilities. Further, any employee manual of the Company shall not change
the terms or conditions of your employment with the Company and shall not create
any contractual rights, including any contractual right to employment for a
definite period of time. The terms and conditions stated herein constitute the
entire offer of employment. Any promises, conditions, perquisites, or statements
made prior to this offer and not expressly stated within this offer of
employment, should not be considered binding upon the Company.

SEVERANCE: In the event the Company terminates your employment without Cause
within the first two years, you will be entitled to a severance payment of six
months of base salary.

CHOICE OF LAW: Your employment will be governed by Texas Law.

CONFIDENTIAL PROVISIONS: You agree to keep the provisions of this offer letter
in confidence and not to disclose its contents to any third party, except your
spouse or domestic partner, your legal counsel, and your financial/tax
accountant, subject to obtaining an obligation from them not to further disclose
such information.

COUNTER-PART EXECUTION: This Offer Letter may be executed in two or more
counter-parts, each which shall be deemed an original, but all of which together
shall constitute but one and the same instrument.

We sincerely look forward to your joining the PetroChemNet Holdings, Inc. team.
This offer is valid until 5:00 p.m. Houston Time on September 7, 1999, unless
extended by mutual agreement. Your anticipated start date would commence no
later than two weeks after your acceptance. You agree that this agreement can be
modified only by written agreement signed by both parties. If this offer
correctly sets forth your understanding and all of the above terms and
conditions are agreeable to you, please indicate your written acceptance below
and return the signed letter to me.


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Very truly yours,


/s/ CARL D. MCCUTCHEON
---------------------
Carl D. McCutcheon
President and Chief Executive Officer
PetroChemNet Holdings, Inc.


I have read and understand and agree with the terms of this offer letter.

Signature: /s/ LAWRANCE W. MCAFEE                       Date: September 7, 1999


Scheduled Start Date: September 20, 1999