Document:

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                                                                    Exhibit 10.4

                                 AMENDMENT NO. 1
                         TO EXCLUSIVE LICENSE AGREEMENT

      Reference is made to a certain Exclusive License Agreement dated March 16,
2001 by and among Regent Court Technologies ("RCT") and Star Scientific, Inc.
("SSI") (hereinafter the "License Agreement").

      For good and valuable consideration, the receipt and sufficiency of which
are hereby acknowledged, RCT and SSI hereby agree to amend the License Agreement
as follows:

      Section 11 is amended so that, in its entirety, it reads as follows.

11. TERMINATION

      11.1 SSI may terminate this Agreement at any time, for any reason, by
providing RCT no less than thirty (30) days prior written notice thereof.

      11.2 RCT may terminate this Agreement upon the occurrence of any of the
following:

      (i) A default in the payment of Royalties when due and payable, or a
failure to submit to RCT when due a true and complete accounting statement
pursuant to Section 5.2 of this Agreement, which default or failure continues
for a period of at least thirty (30) days after RCT has given to SSI written
notice of such default or failure.

      (ii) A material breach of any other obligation of SSI under this
Agreement, which breach shall not have cured within sixty (60) days after RCT
has given to SSI written notice of such breach, in which notice RCT shall have
specified in reasonable detail the nature of such breach. For purposes of
determining materiality, and provided the nature of the breach may be measured
in monetary terms, a breach shall be deemed "material" if such breach results in
a loss of Royalties exceeding $100,000.

      (iii) The purchase of the outstanding stock or assets of SSI.
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      Except as amended hereby, the License Agreement is hereby ratified and
confirmed and the parties acknowledge that it is in full force and effect.

                      Executed this 5th day of April 2001.

                                        REGENT COURT TECHNOLOGIES

                                    By: /s/ Francis E. O'Donnell
                                        ----------------------------------------
                                        Francis E. O'Donnell, General Partner

                                        STAR SCIENTIFIC, INC.

                                    By: /s/ Paul L. Perito
                                        ----------------------------------------
                                        Paul L. Perito, Chairman, President and
                                        Chief Operating Officer

                                       2<PAGE>

                                                                    EXHIBIT 10.5

                                PROMISSORY NOTE
                                ---------------

                                                                 August 20, 2001

     FOR VALUE RECEIVED, Christopher G. Miller ("Maker") promises to pay to Star
Scientific, Inc., a Delaware corporation ("Payee"), the principal sum of
One Hundred Eighty thousand ($180,000.00) on August 20, 2005 (the "Maturity
Date"), together with any interest on the outstanding principal balance
hereunder which shall accrue at the Applicable Interest Rate (as defined below)
commencing on the date hereof and continuing until this Note is paid in full,
subject to adjustment as set forth below, such interest to be payable in arrears
on August 20 of each year that this Promissory Note is outstanding (each an
"Anniversary Date"). Principal and interest hereunder shall be payable in funds
constituting lawful money of the United States of America at the offices of
Payee at 801 Liberty Way, Chester, Virginia, 23836, or such other place
designated in advance in writing by Payee. In case any payment is not made when
due, Maker promises to pay all costs of collection (including reasonable
attorneys' fees) plus interest from the due date until collection in full at the
Applicable Interest Rate plus two percent (2%). The term "Applicable Interest
Rate" shall mean: (1) as of the date hereof, the sum of (a) the Prime Rate as
published in the Wall Street Journal as of the business day immediately
preceding the date hereof plus (b) one percent (1%); and (2) beginning on each
                          ----
Anniversary Date, the sum of (a) the Prime Rate as published in the Wall Street
Journal as of the business day immediately preceding such Anniversary Date plus
                                                                           ----
(b) one percent (1%).

     Maker may prepay the principal amount outstanding under this Promissory
Note in whole or in part from time to time without premium or penalty; provided
that such prepayment of principal is accompanied by payment of all unpaid
interest accrued thereon to the date of such prepayment.

     Maker hereby (a) waives demand, presentment of payment, notice of
nonpayment, protest, notice of protest and all other notice, filing of suit, and
diligence in collecting this Note; (b) agrees to any substitution, addition, or
release of any party or person primarily or secondarily liable hereon; (c)
agrees that the Payee shall not be required first to institute any suit, or to
exhaust its remedies against the Maker or any other person or party to become
liable hereunder, or against any collateral in order to enforce payment of this
Note; (d) consents to any extension, rearrangement, renewal, or postponement of
time of payment of this Note and to any other
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indulgence with respect hereto without notice, consent, or consideration to any
of them; and (e) agrees that, notwithstanding the occurrence of any of the
foregoing (except with the express written release by the Payee or any such
person), the Borrower shall be and remain directly and primarily liable for all
sums due under this Note.

     This Promissory Note shall be governed by the laws of the Commonwealth of
Virginia.

     IN WITNESS WHEREOF, this Promissory Note has been duly executed and
delivered by Maker as of the date hereof.

/s/ David Michael Dean                   /s/ Christopher G. Miller
-------------------------                -------------------------
David Michael Dean                       CHRISTOPHER G. MILLER
Witness<PAGE>

                                                                    EXHIBIT 10.6

                                PROMISSORY NOTE
                                ---------------

                                                                 August 20, 2001

     FOR VALUE RECEIVED, Robert E. Pokusa ("Maker") promises to pay to Star
Scientific, Inc., a Delaware corporation ("Payee"), the principal sum of
On Hundred Forty Thousand Dollars ($140,000.00) on August 20, 2005 (the
"Maturity Date"), together with any interest on the outstanding principal
balance hereunder which shall accrue at the Applicable Interest Rate (as defined
below) commencing on the date hereof and continuing until this Note is paid in
full, subject to adjustment as set forth below, such interest to be payable in
arrears on August 20 of each year that this Promissory Note is outstanding (each
an "Anniversary Date"). Principal and interest hereunder shall be payable in
funds constituting lawful money of the United States of America at the offices
of Payee at 801 Liberty Way, Chester, Virginia, 23836, or such other place
designated in advance in writing by Payee. In case any payment is not made when
due, Maker promises to pay all costs of collection (including reasonable
attorneys' fees) plus interest from the due date until collection in full at the
Applicable Interest Rate plus two percent (2%). The term "Applicable Interest
Rate" shall mean: (1) as of the date hereof, the sum of (a) the Prime Rate as
published in the Wall Street Journal as of the business day immediately
preceding the date hereof plus (b) one percent (1%); and (2) beginning on each
                          ----
Anniversary Date, the sum of (a) the Prime Rate as published in the Wall Street
Journal as of the business day immediately preceding such Anniversary Date plus
                                                                           ----
(b) one percent (1%).

     Maker may prepay the principal amount outstanding under this Promissory
Note in whole or in part from time to time without premium or penalty; provided
that such prepayment of principal is accompanied by payment of all unpaid
interest accrued thereon to the date of such prepayment.

     Maker hereby (a) waives demand, presentment of payment, notice of
nonpayment, protest, notice of protest and all other notice, filing of suit, and
diligence in collecting this Note; (b) agrees to any substitution, addition, or
release of any party or person primarily or secondarily liable hereon; (c)
agrees that the Payee shall not be required first to institute any suit, or to
exhaust its remedies against the Maker or any other person or party to become
liable hereunder, or against any collateral in order to enforce payment of this
Note; (d) consents to any extension, rearrangement, renewal, or postponement of
time of payment of this Note and to any other
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indulgence with respect hereto without notice, consent, or consideration to any
of them; and (e) agrees that, notwithstanding the occurrence of any of the
foregoing (except with the express written release by the Payee or any such
person), the Borrower shall be and remain directly and primarily liable for all
sums due under this Note.

     This Promissory Note shall be governed by the laws of the Commonwealth of
Virginia.

     IN WITNESS WHEREOF, this Promissory Note has been duly executed and
delivered by Maker as of the date hereof.

/s/ Shirwaun Y. Adams                 /s/ Robert E. Pokusa
------------------------              ------------------------
Witness

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