Document:

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                                                                   Exhibit 10.56

                            FIFTH AMENDMENT OF LEASE

         THIS FIFTH AMENDMENT OF LEASE (this "Amendment") is made as of the 1st
day of May, 2001, between VITAMIN REALTY ASSOCIATES, L.L.C. (the "LESSOR), a New
Jersey limited liability company, having an address at 225 Long Avenue,
Hillside, New Jersey 07205, and WIRE ONE TECHNOLOGIES, INC. (the "LESSEE"), a
Delaware corporation, having an address at 225 Long Avenue, Hillside, New Jersey
07205.

                               W I T N E S S E T H

         WHEREAS, pursuant to that certain Lease Agreement dated March 20, 1997
by and between LESSOR and All Communications Corporation, the predecessor of
LESSEE, LESSOR leased to All Communications Corporation certain premises
consisting of approximately 1,560 rentable square feet of warehouse space on the
first floor of the building known as 225 Long Avenue, Hillside, New Jersey (the
"Building"), and approximately 7,180 rentable square feet of office space on the
second floor of the Building (collectively the "Demised Premises"); and

         WHEREAS, pursuant to that certain First Amendment of Lease dated as of
December, 1997, LESSOR and All Communications Corporation amended the Lease to
add to the Demised Premises an additional 5,840 rentable square feet of
warehouse space on the first floor of the Building; and

         WHEREAS, pursuant to that certain Second Amendment of Lease dated as of
December, 1999, LESSOR and All Communications Corporation amended the Lease to
provide that the Demised Premises consisted of a total of 13,730 rentable square
feet of warehouse space on the first floor of the Building, and a total of 8,491
rentable square feet of office space on the second floor of the Building; and

         WHEREAS, pursuant to that certain Third Amendment of Lease dated as of
June 1, 2000, (which, together with the Lease Amendment, First Amendment and
Second Amendment referred to above, shall be referred to herein as the "Lease"),
LESSOR and LESSEE amended the Lease to provide that the Demised Premises
consists of a total of 18,000 rentable square feet of warehouse space on the
first floor of the Building, and a total of 15,215 rentable square feet of
office and warehouse space on the second floor of the Building; and

         WHEREAS, pursuant to that certain Fourth Amendment of Lease dated as of
August 29, 2000, (which, together with the Lease Amendment, First Amendment and
Second Amendment referred to above, shall be referred to herein as the "Lease"),
LESSOR and LESSEE amended the Lease to provide that the Demised Premises
consists of a total of 18,000 rentable square feet of warehouse space on the
first floor of the Building, and a total of 20,954 rentable square feet of
office and warehouse space on the second floor of the Building; and

         WHEREAS, LESSOR and LESSEE have agreed to further amend the Lease, on
the terms and conditions hereinafter set forth; and

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         WHEREAS, all capitalized terms defined in the Lease and not otherwise
defined herein shall have their respective meanings set forth in the Lease.

         NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto do hereby agree that the Lease
is hereby amended as follows:

         1.       (a) Commencing as of May 1, 2001 (the "Expansion Space
Commencement Date"), LESSOR shall demise to LESSEE, and LESSEE shall lease from
LESSOR, an additional 4,800 rentable square feet of warehouse space on the first
floor of the Building and an additional 3,951 rentable square feet of space
located on the second floor of the Building, which is more particularly depicted
in Schedule A attached hereto (the "Expansion Space"). For all purposes of the
Lease, and this Amendment, the term "Demised Premises" shall, as of the
Expansion Space Commencement Date, include the current Demised Premises plus the
Expansion Space.

                  (b) LESSOR and LESSEE each hereby agrees that the Demised
Premises shall, as of the Expansion Space Commencement Date, consequently
consist of a total of 22,800 rentable square feet of warehouse space on the
first floor of the Building, and a total of 24,905 rentable square feet of
office and warehouse space on the second floor of the Building.

         2. Section 1.1(ar) of the Lease is hereby amended to provide that the
Termination Date shall be August 31, 2005.

         3.       (a) Schedule C of the Second Amendment is hereby superseded
and replaced with Schedule B annexed hereto.

                  (b) LESSEE's Proportionate Share with respect to the Demised
Premises shall be 29.82% as of the Expansion Space Commencement Date.

         4. Except as set forth in subsection (a) above, LESSEE agrees that it
has inspected the Expansion Space, and agrees to occupy same in its "AS IS"
condition.

         5. Provided that LESSEE is not in default under the Lease beyond any
applicable notice or cure period, then LESSEE shall have the right to sublease
the portion of the Demised Premises depicted on Schedule A annexed hereto as
Tenant Spaces AA which consists of approximately 3,000 rentable square feet, in
connection with the sale of a division of LESSEE. LESSEE shall deliver to LESSOR
prior written notice of such sublease. LESSOR further waives the recapture right
specified in Section 15.5 of the Lease with respect to any such sublease. Except
as set forth above, such subleasing shall be subject to the provisions of
Article 15 of the Lease.

                                       2
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         6. LESSOR and LESSEE each represents to the other that is has not dealt
with any broker or agent with respect to the Demised Premises or this Lease and
each shall indemnify and hold harmless the other from and against any and all
liabilities, claims, suits, demands, judgments, costs, interests and expenses to
which it may be subject or suffer by reason of any claim made by any person,
firm or corporation for any commission, expense or other compensation as a
result of the execution and delivery of this Lease and based on alleged
conversations or negotiations by said person, firm or corporation with either
LESSOR or LESSEE, as the case may be.

         7. As hereby modified and amended, the Lease shall remain in full force
and effect.

         8. This Amendment and the Lease embody and constitute the entire
understanding between the parties with respect to the subject matter hereof, and
all prior agreements, representations and statements, oral or written, relating
to the subject matter hereof are merged into this Amendment.

         9. Neither this Amendment nor any provision contained herein may be
amended, modified or extended except by an instrument signed by the party
against whom enforcement of such amendment, modifications or extension is
sought.

         10. This Amendment may be executed in counterparts, each of which shall
be deemed a duplicate original hereof.

         IN WITNESS WHEREOF, this Amendment has been executed by LESSOR and
LESSEE as of the day and year first above written.

                                      VITAMIN REALTY ASSOCIATES, L.L.C.

                                      By:
                                               -------------------------------
                                               Name:
                                               Title:

                                      WIRE ONE TECHNOLOGIES, INC.

                                      By:
                                               -------------------------------
                                               Name:
                                               Title:

                                       3
<PAGE>

                                   SCHEDULE B

                                   BASIC RENT

                  The Basic Rent shall be payable in equal monthly installments,
in advance, on the Basic Rent Payment Dates. The Basic Rent for the Term shall
be as follows:

                  (a) for the period from the Commencement Date to, but not
including, the Inclusion Date (defined in the First Amendment), the Basic Rent
shall be $62,680.00 per annum, payable in equal monthly installments of
$5,306.67;

                  (b) for the period from the Inclusion Date to, but not
including, the Amendment Commencement Date (defined in the Second Amendment),
the Basic Rent shall be $87,040.00 per annum, payable in equal monthly
installments of $7,253.33;

                  (c) for the period from the Amendment Commencement Date to,
but not including, the First Additional Space Commencement Date (defined in the
Third Amendment), the Basic Rent shall be $122,846.00 per annum, payable in
equal monthly installments of $10,237,17;

                  (d) for the period from the First Additional Space
Commencement Date to, but not including, the Second Additional Space
Commencement Date (defined in the Third Amendment), the Basic Rent shall be
$139,928.00 per annum, payable in equal monthly installments of $11,660.67;

                  (e) for the period from the Second Additional Space
Commencement Date to, but not including, the Expansion Space Commencement Date
(defined in the Fourth Amendment), the Basic Rent shall be $193,720.00 per
annum, payable in equal monthly installments of $16,143.33;

                  (f) for the period from the Expansion Space Commencement Date
to, but not including the Termination Date, the Basic Rent shall be $259,100.00
per annum, payable in equal monthly installments of $21,591.67;

                  (g) for the period from the Fourth Additional Space
Commencement Date to, but not including, the Termination Date, the Basic Rent
shall be $316,268.00 per annum, payable in monthly installments of $26,355.67.

                                       4<PAGE>

                                                                   Exhibit 10.57

                            SIXTH AMENDMENT OF LEASE

         THIS SIXTH AMENDMENT OF LEASE (this "Amendment") is made as of the 1st
day of May, 2002, between VITAMIN REALTY ASSOCIATES, L.L.C. (the "LESSOR), a New
Jersey limited liability company, having an address at 225 Long Avenue,
Hillside, New Jersey 07205, and WIRE ONE TECHNOLOGIES, INC. (the "LESSEE"), a
Delaware corporation, having an address at 225 Long Avenue, Hillside, New Jersey
07205.

                               W I T N E S S E T H

         WHEREAS, pursuant to that certain Lease Agreement dated March 20, 1997
by and between LESSOR and All Communications Corporation, the predecessor of
LESSEE, LESSOR leased to All Communications Corporation certain premises
consisting of approximately 1,560 rentable square feet of warehouse space on the
first floor of the building known as 225 Long Avenue, Hillside, New Jersey (the
"Building"), and approximately 7,180 rentable square feet of office space on the
second floor of the Building (collectively the "Demised Premises"); and

         WHEREAS, pursuant to that certain First Amendment of Lease dated as of
December, 1997, LESSOR and All Communications Corporation amended the Lease to
add to the Demised Premises an additional 5,840 rentable square feet of
warehouse space on the first floor of the Building; and

         WHEREAS, pursuant to that certain Second Amendment of Lease dated as of
December, 1999, LESSOR and All Communications Corporation amended the Lease to
provide that the Demised Premises consisted of a total of 13,730 rentable square
feet of warehouse space on the first floor of the Building, and a total of 8,491
rentable square feet of office space on the second floor of the Building; and

         WHEREAS, pursuant to that certain Third Amendment of Lease dated as of
June 1, 2000, LESSOR and LESSEE amended the Lease to provide that the Demised
Premises consists of a total of 18,000 rentable square feet of warehouse space
on the first floor of the Building, and a total of 15,215 rentable square feet
of office and warehouse space on the second floor of the Building; and

         WHEREAS, pursuant to that certain Fourth Amendment of Lease dated as of
August 29, 2000, LESSOR and LESSEE amended the Lease to provide that the Demised
Premises consists of a total of 18,000 rentable square feet of warehouse space
on the first floor of the Building, and a total of 20,954 rentable square feet
of office and warehouse space on the second floor of the Building; and

         WHEREAS, pursuant to that certain Fifth Amendment of Lease dated as of
May 1, 2001 (a copy of which is attached, and which, as modified herein, LESSOR
and LESSEE hereby confirm, and which, together with the Lease Agreement, First
Amendment, Second Amendment, Third Amendment and Fourth Amendment referred to
above, shall collectively be referred to herein as the "Lease"), LESSOR and
LESSEE amended the Lease to provide that the Demised Premises consists of a
total of 22,800 rentable square feet of warehouse space on the first floor of
the Building, and a total of 24,905 rentable square feet of office and warehouse
space on the second floor of the Building.

<PAGE>

         WHEREAS, LESSOR and LESSEE have agreed to further amend the Lease, on
the terms and conditions hereinafter set forth; and

         WHEREAS, all capitalized terms defined in the Lease and not otherwise
defined herein shall have their respective meanings set forth in the Lease.

         NOW, THEREFORE, in consideration of the mutual covenants contained
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto do hereby agree that the Lease
is hereby amended as follows:

         1.       (a) Effective as of May 1, 2002 (the "Contraction Space
Commencement Date"), LESSOR shall recapture from LESSEE, and LESSEE shall
surrender to LESSOR, 19,800 rentable square feet of warehouse space on the first
floor of the Building (the "Surrendered Warehouse Space") and 8,791 rentable
square feet of space located on the second floor of the Building (such
surrendered space, collectively, the "Contraction Space"). For all purposes of
the Lease, including this Amendment, the term "Demised Premises" shall, as of
the Contraction Space Commencement Date, consist of the Demised Premises prior
to that Date less the Contraction Space.

                  (b) LESSOR and LESSEE each hereby agrees that the Demised
Premises shall, as of the Contraction Space Commencement Date, consequently
consist of a total of 3,000 rentable square feet of warehouse space on the first
floor of the Building, and a total of 16,114 rentable square feet of office
space on the second floor of the Building, which Demised Premises are more
particularly depicted in Schedule A hereto.

         2. Section 1.1(ar) of the Lease is hereby amended to provide that the
Termination Date shall be April 30, 2005. LESSEE shall have the option to renew
the Lease for an additional three-year term, commencing May 1, 2005, on the same
terms and conditions prevailing under the Lease at April 30, 2005, with the
exception that the Basic Rent shall during such additional three-year term be
$193,754.00 per annum, payable in monthly installments of $16,146.17.

         3.       (a) Schedule B of the Fifth Amendment is hereby superseded and
replaced, effective as of May 1, 2001, with Schedule B annexed hereto. LESSEE
shall, in addition to any Additional Rent otherwise due under the Lease, pay to
LESSOR, for each of the six months commencing as of the Contraction Space
Commencement Date, (i) the amount of $6,675 and (ii) the amount of Additional
Rent that would have been payable by LESSEE in respect of utilities charges and
other building operating expenses allocable to the Surrendered Warehouse Space
for such month.

                  (b) LESSEE's Proportionate Share with respect to the Demised
Premises shall be 12% as of the Contraction Space Commencement Date.

                                       2
<PAGE>

         4. Except as set forth in subsection (a) above, LESSEE agrees that it
has inspected the Demised Premises, and agrees to occupy same in its "AS IS"
condition.

         5. LESSOR and LESSEE each represents to the other that is has not dealt
with any broker or agent with respect to the Demised Premises or this Lease and
each shall indemnify and hold harmless the other from and against any and all
liabilities, claims, suits, demands, judgments, costs, interests and expenses to
which it may be subject or suffer by reason of any claim made by any person,
firm or corporation for any commission, expense or other compensation as a
result of the execution and delivery of this Lease and based on alleged
conversations or negotiations by said person, firm or corporation with either
LESSOR or LESSEE, as the case may be.

         6. As hereby modified and amended, the Lease shall remain in full force
and effect.

         7. This Amendment and the other components of the Lease embody and
constitute the entire understanding between the parties with respect to the
subject matter hereof, and all prior agreements, representations and statements,
oral or written, relating to the subject matter hereof are merged therein.

         8. Neither this Amendment nor any provision contained herein may be
amended, modified or extended except by an instrument signed by the party
against whom enforcement of such amendment, modifications or extension is
sought.

         9. This Amendment may be executed in counterparts, each of which shall
be deemed a duplicate original hereof.

         IN WITNESS WHEREOF, this Amendment has been executed by LESSOR and
LESSEE as of the day and year first above written.

                                        VITAMIN REALTY ASSOCIATES, L.L.C.

                                        By:
                                                 ------------------------------
                                                 Name:  Eric Friedman
                                                 Title: Member

                                        WIRE ONE TECHNOLOGIES, INC.

                                        By:
                                                 ------------------------------
                                                 Name:  Jonathan Birkhahn
                                                 Title: EVP Business Affairs and
                                                        General Counsel

                                       3
<PAGE>

                                   SCHEDULE B

                                   BASIC RENT

                  The Basic Rent shall be payable in equal monthly installments,
in advance, on the Basic Rent Payment Dates. The Basic Rent for the Term shall
be as follows:

                  (a) for the period from the Commencement Date to, but not
including, the Inclusion Date (defined in the First Amendment), the Basic Rent
shall be $62,680.00 per annum, payable in equal monthly installments of
$5,306.67;

                  (b) for the period from the Inclusion Date to, but not
including, the Amendment Commencement Date (defined in the Second Amendment),
the Basic Rent shall be $87,040.00 per annum, payable in equal monthly
installments of $7,253.33;

                  (c) for the period from the Amendment Commencement Date to,
but not including, the First Additional Space Commencement Date (defined in the
Third Amendment), the Basic Rent shall be $122,846.00 per annum, payable in
equal monthly installments of $10,237,17;

                  (d) for the period from the First Additional Space
Commencement Date to, but not including, the Second Additional Space
Commencement Date (defined in the Third Amendment), the Basic Rent shall be
$139,928.00 per annum, payable in equal monthly installments of $11,660.67;

                  (e) for the period from the Second Additional Space
Commencement Date to, but not including, the Expansion Space Commencement Date
(defined in the Fourth Amendment), the Basic Rent shall be $193,720.00 per
annum, payable in equal monthly installments of $16,143.33;

                  (f) for the period from the Expansion Space Commencement Date
to, but not including, May 1, 2001, the Basic Rent shall be $259,100.00 per
annum, payable in equal monthly installments of $21,591.67;

                  (g) for the period from May 1, 2001, to, but not including,
the Contraction Space Commencement Date, the Basic Rent shall be $316,268.00 per
annum, payable in monthly installments of $26,355.67; and

                  (h) for the period from the Contraction Space Commencement
Date to, and including, the Termination Date, the Basic Rent shall be
$161,526.00 per annum, payable in monthly installments of $13,460.50.

                                       4

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