EXHIBIT 10.12



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                 AMENDED AND RESTATED TERM LOAN PROMISSORY NOTE

$288.888.96                                                        July 10, 2000

         FOR  VALUE  RECEIVED,   AVATAR  SYSTEMS,   INC.,  a  Texas  corporation
("Borrower"),  promises to pay to the order of BANK ONE, TEXAS, N.A.  ("Payee"),
pursuant to the terms and conditions set forth herein, TWO HUNDRED  EIGHTY-EIGHT
THOUSAND EIGHT HUNDRED EIGHTY-EIGHT and 96/100 DOLLARS  ($288,888.96).  Borrower
also promises to pay interest on the unpaid principal amount of this Amended and
Restated Term Loan  Promissory  Note (this "Note") at the rates and at the times
set forth below:

         Rate of  Interest.  Absent  an Event of  Default  as  provided  in that
certain Amended and Restated Loan Agreement executed by and between Borrower and
Payee,  dated as of even date herewith (the "Loan Agreement";  capitalized terms
used herein without  definition shall have the meanings  assigned to them in the
Loan Agreement), the unpaid principal balance of the Note shall bear interest at
an annual rate equal to the lesser of (a) the Bank Rate plus one  percent  (1%),
or (b) the highest rate permitted by applicable laws (the "Maximum  Rate").  The
"Bank  Rate"  shall  mean the per annum rate of  interest  (rounded  upward,  if
necessary,  to the nearest 0. 0 1 %)  announced  or quoted by Payee from time to
time as its prime rate for commercial  loans to its customers,  as determined by
Payee (with the understanding  that such rate may merely be a reference rate and
may not  necessarily  represent the lowest or best rate actually  charged to any
customer  by Bank).  Interest  on this Note shall be  computed on the basis of a
year of 360 days and the actual number of days elapsed  (including the first day
but excluding the last day) unless such  calculation  would result in a usurious
rate, in which case  interest  shall be calculated on the basis of a year of 365
or 366 days, as the case may be.

         Scheduled  Payments  of  Principal  and  Interest.  Accrued  and unpaid
interest  shall be due and  payable  on the first day of each  month  hereafter.
Unless sooner due and payable,  or unless  accelerated,  as provided in the Loan
Agreement,  the unpaid principal balance of the Note shall be due and payable in
twenty (20) equal monthly installments of $14,444.44,  commencing July 31, 2000,
and continuing  through February 28, 2002 (the "Maturity Date"). On the Maturity
Date,  a final  payment of all accrued and unpaid  interest on the Note shall be
due and payable.  All payments of principal  and interest due in respect to this
Note shall be made  without  deduction,  defense,  set-off or  counterclaim,  in
lawful  money  of the  United  States  of  America,  and in same day  funds  and
delivered to Payee at 1717 Main Street, 4th Floor,  Dallas,  Texas, 75201, or at
such other place as shall be designated by notice for such purpose in accordance
with the terms of the Loan Agreement.

         Whenever  any  payment of  principal  or interest on this Note shall be
stated to be due on a day other  than a day when Payee is open for  business  (a
"Business Day"), such payment shall be made on the next succeeding  Business Day
and such  extension of time shall be included in the  computation of the payment
of interest on this Note.

         Payment  Upon  Event of  Default.  Upon the  occurrence  of an Event of
Default,  (i) the unpaid balance of the principal amount of this Note,  together
with all interest  accrued hereon may become,  or may be declared to be, due and
payable in the manner,  upon the conditions and with the effect  provided in the
Loan Agreement and Loan  Documents.  Upon an Event of Default,  and beginning on
the date of such  Event of  Default,  the unpaid  principal  balance of the Note
shall bear interest at the Maximum Rate.

AMENDED AND RESTATED TERM LOAN PROMISSORY NOTE-PAGE 1

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         Payment of  Expenses/Waivers.  Borrower  promises  to pay all costs and
expenses,  including reasonable attorneys' fees, incurred in the collection and,
enforcement  of  this  Note.  Borrower  hereby  waives  diligence,  presentment,
protest, demand, notice of intent to accelerate,  notice of acceleration and any
other notice of every kind  (except  such  notices as may be required  under the
Loan Agreement) and, to the full extent permitted by law, the right to plead any
statute of limitations as a defense to any demand hereunder.

         Maximum Rate of Interest. Regardless of any provision contained in this
Note, the holder hereof shall never be entitled to receive, collect or apply, as
interest on this Note,  any amount in excess of the highest  rate  permitted  by
applicable laws (the "Maximum  Rate"),  and, if the holder hereof ever receives,
collects,  or applies as  interest,  any such amount  which  would be  excessive
interest,  it shall be deemed a partial  prepayment  of  principal  and  treated
hereunder as such; and, if the  indebtedness  evidenced  hereby is paid in full,
any remaining excess shall forthwith be paid to Borrower. In determining whether
or not the interest paid or payable, under any specific contingency, exceeds the
Maximum  Rate,  Borrower  and the holder  hereof  shall,  to the maximum  extent
permitted under applicable law (1) characterize any non-principal  payment as an
expense,  fee or  premium  rather  than  as  interest,  (ii)  exclude  voluntary
prepayments  and the  effects  thereof,  and (111)  spread  the total  amount of
interest throughout the entire contemplated term of the obligations evidenced by
this Note and/or  referred to in the Loan Agreement so that the interest rate is
uniform throughout the entire term of this Note;  provided that, if this Note is
paid  and  performed  in full  prior to the end of the  fall  contemplated  term
thereof, and if the interest received for the actual period of existence thereof
exceeds the Maximum Rate,  the holder hereof shall refund to Borrower the amount
of such  excess or credit the amount of such  excess  against  the  indebtedness
evidenced hereby,  and, in such event, the holder hereof shall not be subject to
any  penalties  provided  by any laws for  contracting  for,  charging,  taking,
reserving or receiving interest in excess of the Maximum Rate.

         THIS NOTE SHALL BE GOVERNED BY AND SHALL BE  CONSTRUED  AND ENFORCED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS.

         THIS NOTE, THE LOAN  AGREEMENT AND THE OTHER LOAN  DOCUMENTS  REPRESENT
THE FINAL AGREEMENTS BETWEEN THE PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE
OF PRIOR,  CONTEMPORANEOUS,  OR SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE
ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN THE PARTIES.

         This Note amends,  modifies and restates, but does not extinguish,  the
indebtedness  evidenced by that certain Term Loan Promissory  Note,  dated as of
August 26, 1998, in the stated  principal amount of Five Hundred Twenty Thousand
Dollars and No Cents  ($520,000.00),  executed by Avatar Systems,  Ltd., a Texas
limited partnership, and payable to the order of Payee.

                            (Signature Page Follows)

AMENDED AND RESTATED TERM LOAN PROMISSORY NOTE-PAGE 2

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         IN WITNESS  WHEREOF,  Borrower  has caused this Note to be executed and
delivered by its duly authorized  officer,  as of the day and year first written
above.

                                       AVATAR SYSTEMS, INC.,
                                       a Texas corporation


                                       By /s/ Robert C. Shreve, Jr.
                                          --------------------------------------
                                       Name:    Robert C. Shreve, Jr.
                                       Title:   President



AMENDED AND RESTATED TERM LOAN PROMISSORY NOTE - Signature Page