<PAGE>
EXHIBIT 10.25
(GE LOGO)
GE CAPITAL
COMMERCIAL EQUIPMENT FINANCING
LEAH A. SMITH
2400 E. Katella Avenue
Senior Risk Analyst
Suite 800
Anaheim, CA 92806
714-456-9449 / Fax:
714-456-9473
Internet:
leah.smith@ge.com
December 31, 2003
Mr. Arthur T. Taylor
Chief Financial Officer
Terayon Communication Systems, Inc.
4988 Great America Parkway
Santa Clara, CA 95054
RE: Aircraft
Lease Agreement between General Electric Capital Corporation
("Lessor") and Terayon Communication Systems, Inc. ("Lessee")
dated
February 8, 2002 (the "Lease")
Dear Mr. Taylor:
Annex B to the Lease is hereby amended as
follows:
<Table>
<S>
<C>
<C>
B. 1. Advance Rent (if any): (a) Amount: $179,225.93
(b) Due Date: January
1, 2004
(Previously paid as part of
invoice # 10024489 dated
November 5, 2003. No
payment
due January 1, 2004.)
B. 15. Basic Term Lease Rate Factor:
Factor
Rental No.
1.846198%
9-19
B. 16. Base Index Rate: 1.03%
</Table>
<PAGE>
Exhibit I to Annex B to the Lease is hereby
amended as follows:
<Table>
<Caption>
Floating
Rate
Payment
Adjustment
Number
Factor
-------
----------
<S>
<C>
9
8.7572
10
7.9280
11
7.3276
12
6.7255
13
6.2298
14
5.7431
15
5.2873
16
4.8299
17
4.4012
18
3.8913
19
3.4165
20
2.0594
</Table>
Annex F to the Lease is hereby amended as
follows:
<Table>
<Caption>
# of
Base
Termination
Payments
Value
--------
-----------
<S>
<C>
9
97.449
10
96.391
11
95.142
12
93.854
13
92.642
14
91.530
15
90.452
16
89.350
17
88.225
18
87.078
19
85.905
20
84.711
</Table>
In addition, Lessor agrees that upon
delivery to Lessor of a security deposit
pledge in the amount of Seven Million Four
Hundred Ninety-Eight Thousand Nine
Hundred Eighty and 56/100 Dollars
($7,498,980.56), in the form and substance
acceptable to Lessor, Lessor shall release
to Lessee all letters of credit
currently held by Lessor as security for
obligations under the Lease.
<PAGE>
Except as expressly modified hereby, all
terms and provisions of the Lease shall
remain in full force and effect.
If you have any questions or concerns
regarding the above, please do not
hesitate to contact me at (714)
456-9449.
Sincerely,
/s/ Leah A. Smith
Leah A. Smith
Senior Risk Analyst
Accepted and agreed to:
Terayon Communication Systems, Inc.
By: /s/ Arthur T. Taylor
-------------------------------
Name: Arthur T. Taylor
-----------------------------
Title: Chief Financial Officer
----------------------------
Date: December 31, 2003
-----------------------------
<PAGE>
(GE LOGO)
GE CAPITAL
COMMERCIAL EQUIPMENT FINANCING
LEAH A. SMITH
2400 E. Katella Avenue
Senior Risk Analyst
Suite 800
Anaheim, CA 92806
714-456-9449 / Fax:
714-456-9473
Internet:
leah.smith@ge.com
December 31, 2003
Mr. Arthur T. Taylor
Chief Financial Officer
Terayon Communication Systems, Inc.
4988 Great America Parkway
Santa Clara, CA 95054
RE: Aircraft
Lease Agreement between General Electric Capital Corporation
("Lessor") and Terayon Communication Systems, Inc. ("Lessee")
dated
February 8, 2002 (the "Lease")
Dear Mr. Taylor:
Annex B to the Lease is hereby amended as
follows:
G. AMENDMENTS TO LEASE.
Lessee has the
option to extend the Basic Term by one month without
additional
charge upon 30-days written notice to Lessor.
Except as expressly modified hereby, all
terms and provisions of the Lease and
related documents shall remain in full
force and effect. Indicate your agreement
to the terms hereof by signing this letter
where indicated below. Failure to
return a signed original to Lessor shall
render this letter null and void, and
of no further force or effect.
If you have
