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                                                                   Exhibit 10.33

EXTENSION TO THE A.I.R. STANDARD INDUSTRIAL/COMMERCIAL SINGLE TENANT LEASE - NET
DATED NOVEMBER 11, 1997 BY AND BETWEEN KENNETH R. SMITH AND ALICE J. SMITH AS
LESSOR AND LUMINENT, INC., A SUBSIDIARY OF MRV COMMUNICATIONS INC. AS LESSEE FOR
THE PROPERTY COMMONLY KNOWN AS 8917 FULLBRIGHT AVENUE, CHATSWORTH, CALIFORNIA
DRAFTED September 25.2002.

55.      Lessor and Lessee agree to extend the original Lease for an additional
         five (5) years, commencing January 1, 2003 and ending December 31,
         2008. The base rent per month stated in Paragraph 1.5 shall be adjusted
         to $4,250.00.

56.      The Base Rent stated in Paragraph 1.5 shall be adjusted annually on
         January 1st of each succeeding year by a fixed three percent (3%).

57.      Option to Extend. Lessor hereby grants to Lessee the option to extend
         the term of this lease for one (1) additional thirty-six (36) month
         period commencing when the prior term expires upon each and all of the
         following terms and conditions.

         (i)      In order to exercise an option to extend, Lessee must give
                  written notice of such election to Lessor and Lessor must
                  receive the same at least six (6) but not more than nine (9)
                  months prior to the date that the option period would
                  commence, time being of the essence. If proper notification of
                  the exercise of an option is not given and/or received, such
                  option shall automatically expire.

         (ii)     The provisions of paragraph 39, including those relating to
                  Lessee's Default set forth in paragraph 39.4 of this Lease,
                  are conditions of this Option.

         (iii)    Except for the provisions of this Lease granting an option or
                  options to extend the term, all of the terms and conditions of
                  this Lease except where specifically modified by this option
                  shall apply.

         (iv)     This Option is personal to the original Lessee, and cannot be
                  assigned or exercised by anyone other than said original
                  Lessee and only while the original Lessee is in full
                  possession of the Premises and without the intention of
                  thereafter assigning or subletting.

         (v)      The monthly rent for each of the option period shall be
                  calculated as per paragraph 56 above.

AGREED AND ACCEPTED:

LESSEE                                              LESSOR

     /s/ Noam Lotan                                 /s/ Kenneth R. Smith
-----------------------------                        -----------------------
Noam Lotan, President & C.E.O                        Kenneth R. Smith, Owner

     /s/ Shay Gonen                                 /s/ Alice J. Smith
-----------------------------                        -----------------------
Shay Gonen, CFO                                      Alice J. Smith, Owner

         10/18/02                                          10-21-02
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Date