INFOCROSSING, INC. AND SUBSIDIARIES
                                  EXHIBIT 10.6A

                           TENTH FLOOR OPTION AGREEMNT

         AGREEMENT made as of the 30th day of November, 1999, by and among G-H-G
REALTY COMPANY, L.L.C., a limited liability company formed in accordance with
the laws of the State of New York (successor to G-H-G Realty Company, a
partnership), having an office at 360 West 31st Street, New York, New York 10001
(hereinafter referred to as "Landlord"); RSL COM U.S.A., INC., a Delaware
corporation, having an office at 430 Park Avenue, New York, New York 10022
(hereinafter referred to as "Subtenant"); and COMPUTER OUTSOURCING SERVICES,
INC. (formerly known as Commercial Online Systems, Inc.), a Delaware corporation
having an office at 2 Christie Heights Street, Leonia, New Jersey 07605
(hereinafter referred to as "COSI").

                              W I T N E S S E T H:

         WHEREAS, the Landlord previously entered into an Agreement of Lease
dated January 24, 1991 with COSI with respect to certain space on the Tenth
(10th) and Eleventh (11th) Floors and certain basement space in the building
known as 360 West 31st Street, New York, New York (the "Building") (the said
Agreement of Lease together with five (5) separate supplemental agreements by
and between the parties thereto being collectively referred to herein as "the
Lease"); and

         WHEREAS, COSI thereafter entered into an Agreement of Sublease dated
July 1998 with the Subtenant (the "Sublease"), pursuant to which COSI sublet to
Subtenant the entire Eleventh (11th) Floor of the Building (the "Eleventh Floor
Premises") consisting of approximately 22,300 rentable square feet and part of
the Tenth (10th) Floor (the "Tenth Floor Premises") of the Building, consisting
of approximately 9,200 rentable square feet (the Eleventh Floor Premises and the
Tenth Floor Premises being collectively referred to herein as the "Demised
Premises"); and

         WHEREAS, Subtenant, as a condition of Landlord's consent to Sublease,
agreed to be subject and subordinate at all times to all covenants, agreements,
terms, provisions and conditions of the Lease and of a certain Consent to
Sublease dated September 14, 1998 (the "Consent"); and

         WHEREAS, the parties have entered into a certain agreement of even date
herewith (the "Eleventh Floor Option Agreement") pursuant to which COSI and
Subtenant have granted to Landlord an option (the "Eleventh Floor Option") to
take back the Eleventh Floor Premises, which option shall expire on December 3,
1999 (the "Eleventh Floor Option Expiration Date"); and

         WHEREAS, Landlord has requested an option to take back the Tenth Floor
Premises, and COSI and Subtenant desire to grant such option to Landlord on the
terms and conditions set forth herein.

         NOW, THEREFORE, in consideration of the mutual obligations of the
parties hereto, and other good and valuable consideration, receipt of which is
acknowledged by each of them, the parties hereby covenant and agree as follows:

         1. Grant of Option. Subtenant and COSI hereby grant Landlord the option
(the "Tenth Floor Option"), expiring on February 15, 2000 (the "Tenth Floor
Option Expiration Date") to take back the Tenth Floor Premises.

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         2. Manner of Exercise. The Tenth Floor Option may be exercised only by
delivery of written notice of such exercise to Subtenant and COSI prior to the
Tenth Floor Option Expiration Date. Such notice shall be deemed given on the
date of actual receipt thereof by Subtenant and COSI (such date being referred
to herein as the "Tenth Floor Option Exercise Date").

         3.       Consideration.   In  the  event  that  the  Landlord   elects
                  -------------
to exercise the Tenth Floor Option, Subtenant shall pay the total sum of Eighty
Seven Thousand ($87,000.00) Dollars, ("Consideration") as follows:

a.       To the Landlord, the sum of Twelve Thousand Dollars ($12,000.00);

b.       To S.L. Green Leasing, Inc., the sum of Fifty Two Thousand Five Hundred
Dollars ($52,500.00);

c.       To COSI, the sum of Twenty Two Thousand Five Hundred Dollars
($22,500.00).

         4.       Payment.        The aforementioned payments shall be made
                  -------
within five (5) business days after receipt by Subtenant and COSI of notice of
exercise of the Tenth Floor Option. If such payments are not timely made, they
shall accrue interest at the highest rate permitted by law. In the event that
Landlord, COSI, or S.L. Green Leasing, Inc. as the case may be, is required to
expand any sums, including but not limited to reasonable legal fees, to collect
any such payment, Subtenant shall, in addition to all other payments required
hereunder, be liable for all such costs and expenses.

5.       Termination of Sublease; Mutual Release.
         ---------------------------------------

A.       The Sublease shall automatically be deemed cancelled and terminated in
full, effective as of the Tenth Floor Option Exercise Date, and Subtenant shall
have no further liability whatsoever to COSI or Landlord as of the Tenth Floor
Option Exercise Date, arising out of the Sublease, the Lease, the Consent or
otherwise, all of which liabilities are hereby released, except for rent or
other obligations under the Sublease accruing prior to the Tenth Floor Option
Exercise Date and the Consideration payment obligations set forth herein.

                  B. Effective as of the Tenth Floor Option Exercise Date,
Subtenant releases COSI from all liability under the Sublease, except for
obligations or liabilities of COSI accruing thereunder on or after December 1,
1999.

         6. COSI Liability. Upon the Tenth Floor Option Exercise Date, COSI
shall continue to be liable for the rent and additional rent due under the Lease
but for no other obligations thereunder, the Landlord releasing COSI from all
claims, obligations, actions, suits and the like under the Lease except COSI's
liability for the rent and additional rent thereunder as limited herein and
except for obligations under the lease, if any, arising prior to the Tenth Floor
Option Exercise Date; provided, however, that effective as of the Tenth Floor
Option Exercise Date, the liability of COSI thereunder shall be reduced by an
amount equal to the amount of the liability of Subtenant under the Sublease for
rent and additional rent which shall have been eliminated pursuant to the
provisions of the Eleventh Floor Option Agreement and this Tenth Floor Option
Agreement.

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         7. Refund of Security. Simultaneously with the receipt of the payment
to be made to it pursuant to paragraph "3" hereof, COSI shall take all steps as
may be required to permit all security remaining on deposit, or otherwise posted
by, Subtenant under the sublease to be released to Subtenant.

         8.       Brokerage   Commission.   Subtenant   shall  have  no
                  ----------------------
liability  for  any   brokerage   commission  in connection with this
transaction  other than as set forth in Paragraph 3(b) hereof.  Subtenant shall,
however,  pay any commission  which may be due any broker,  other than S.L.
Green Leasing,  Inc., with whom Subtenant may have dealt.  COSI shall have no
liability for any brokerage commission in connection with this transaction.

         9. Expiration of Eleventh Floor Option. In the event that the Landlord
fails to exercise the Eleventh Floor Option on or before the Eleventh Floor
Option Expiration date, this Tenth Floor Option Agreement shall immediately
cease to be of any further force or effect, and shall be deemed cancelled and
terminated, as of the Eleventh Floor Option Expiration Date.

         10. Expiration of Tenth Floor Option. In the event that the Landlord
shall exercise the Eleventh Floor Option, but shall fail to exercise the Tenth
Floor Option on or before the Tenth floor Option Expiration Date, this Agreement
shall immediately cease to be of any further force or effect, and shall be
deemed cancelled and terminated, as of the Tenth Floor Option Expiration Date.

         11.      Third  Party  Beneficiary.  S.L.  Green  Leasing,  Inc.  Shall
                  -------------------------
 be deemed a third party  beneficiary  of paragraphs "3" and "4" of this
Agreement.

         IN WITNESS WHEREOF, the parties have duly executed this Agreement as of
this 30th day of November, 1999.


                        G-H-G REALTY COMPPANY, LLC, Landlord

                                /s/ Bruce Gittlin
             By:      _______________________________________

                       RSL COM U.S.A., INC., Subtenant

                            /s/ Ruth Fisher
              By:     _______________________________________
                           Vice President

                        COMPUTER OUTSOURCING SERVICES, INC.

                         /s/ Nicolas J. Letizia
              By:     ________________________________________
                        Chief Financial Officer







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                              G-H-G REALTY COMPANY
                           21 PENN PLAZA o SUITE 1000
                              360 WEST 31ST STREET
                               NEW YORK, NY 10001
                                 (212) 244-4646

                                                            February 14, 2000



BY: HAND DELIVERY

Computer Outsourcing Services, Inc.
2 Christie Heights Street
Leonia, NJ 07605

RSL Com U.S.A., Inc.
430 Park Avenue
New York, NY 10022

Gentlemen:

In accordance with Paragraph 2. of the 10th Floor Option Agreement between us,
made as of the 30th day of November 1999 (the "Agreement"), this letter will
serve to formally notify you that we have elected to exercise the 10th Floor
Option set forth in Paragraph 1. of the Agreement.

Please note that in accordance with Paragraph 4. of the Agreement, RSL is
required to make the payments referred to in Paragraph 3. of the Agreement
within five (5) business days after receipt of this notice.


                                                              Very truly yours,

                                                 G-H-G REALTY COMPANY, L.L.C.
                                           By: G-H-G Realty Management Co., Inc.
                                                       Management Member


                                                      /s/ Bruce D. Gittlin
                                                       -------------------
                                                        Bruce D. Gittlin
                                                            President













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