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                                                                   EXHIBIT 10.23

                            FIRST AMENDMENT TO LEASE

         LM VENTURE, LLC, a Delaware limited liability company ("Landlord") and
EMULEX CORPORATION, a California corporation ("Tenant"), hereby amend that
certain Real Estate Lease between them dated September 12, 2000 (the "Lease") as
set forth below. Unless otherwise indicated, capitalized terms used in this
Amendment shall have the meanings set forth in the Lease.

         1.       LEASE OF ADDITIONAL PREMISES. Subject to the terms of the
Lease as amended hereby, Landlord leases to Tenant, and Tenant leases from
Landlord, the 13,587 square feet of space in the Building which is adjacent to
the Premises on the west as delineated on Exhibit A attached hereto (referred to
herein separately from the original Premises as the "Additional Premises"). The
Additional Premises shall be added to the original Premises for all purposes of
the Lease. THE COMMENCEMENT DATE FOR THE ORIGINAL PREMISES AND THE ADDITIONAL
PREMISES SHALL BE THE DATE OF SUBSTANTIAL COMPLETION AS DEFINED IN SECTION 2.03
OF THE LEASE. LANDLORD ACKNOWLEDGES THAT, AS OF THE DATE OF THE MUTUAL EXECUTION
OF THIS AMENDMENT, TENANT HAS NOT DELAYED OR IN ANY WAY FAILED TO MEET THE
TIMELINES FOR APPROVAL SET FORTH IN ARTICLE II OF THE LEASE.

         2.       BASE RENT. Base Rent for the Additional Premises shall be
$12.75 per square foot per annum for the first year of the Lease Term; $13.13
per square foot per annum for the second year of the Lease Term; $13.53 per
square foot per annum for the third year of the Lease Term; $13.93 per square
foot per annum for the fourth year of the Lease Term; and $14.35 per square foot
per annum for the fifth year of the Lease Term.

         3.       SUBMISSION OF SPACE PLAN; CONSTRUCTION. Tenant shall, as soon
as reasonably possible but in any event within 30 days after full execution of
this Amendment, provide Tenant's Specifications for the Premises to Landlord for
preparation of Premises Construction Documents and construction by Landlord of
the Premises in accordance with the Lease. Promptly after construction plans for
the Premises are prepared and approved as provided in the Lease, Landlord shall
complete construction of the Premises in accordance with the approved plans.

         4.       FINISH ALLOWANCE.

                  (a)      Landlord shall contribute an amount equal to $20.00
         per square foot of the Additional Premises (the "Additional Allowance")
         to cover costs associated with design and construction of Tenant
         Improvements to the Additional Premises (including electrical and
         engineering costs beyond Landlord's Work described in Exhibit C to the
         Lease and architectural costs beyond preparation of the initial space
         plan). Landlord and Tenant shall compare the total expenditures for
         these Tenant Improvements with the total amount of the Additional
         Allowance. If such expenditures are less than the Additional Allowance,
         Base Rent for the Additional Premises shall be reduced by the amount of
         such difference amortized over the initial Lease Term at the rate of
         12% per annum.

                  (b)      To the extent that costs associated with design and
         construction exceed $20.00 per square foot (as to the Additional
         Premises) or $21.00 (as to the original such expenditures are in excess
         of the Additional Allowance, Tenant may in each case elect to

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         have Base Rent increased by an amount equal to all or a portion of such
         excess costs (not exceeding $7.00 per square foot) at the rate of 12%
         per annum ($.12 per square foot per dollar of excess costs). Tenant
         shall be solely responsible for paying all such excess costs which are
         not incorporated into Base Rent pursuant to the previous sentence. For
         example, if the total cost of Tenant Improvements to the Additional
         Premises is $23.00 per square foot, Base Rent for the Additional
         Premises for the first Lease Year may, at Tenant's election, be
         increased by $.36 to $13.11 per square foot, which would be increased
         at an annual rate of 3% to determine Base Rent for the Additional
         Premises for subsequent Lease Years.

                  (c)      If, based on the approved budget, any portion of the
         cost of Tenant Improvements to the Premises will exceed the Tenant
         Allowance or the Additional Allowance (as applicable) and will not be
         incorporated into Base Rent pursuant to subparagraph (b) above, such
         portion shall be divided by the total cost of the Tenant Improvements
         to the applicable space to determine the portion ("Tenant's
         Percentage") which shall be the sole responsibility of Tenant. During
         the course of construction of the Tenant Improvements, Tenant shall pay
         to Landlord, within 10 days after receipt of a statement of the cost of
         the Tenant Improvements during any month, an amount equal to Tenant's
         Percentage of such monthly costs which are attributable to the space
         involved. When all Tenant Improvements have been completed and paid
         for, Landlord and Tenant shall reconcile the total expenditures for the
         Tenant Improvements to the total amount of the Tenant Allowance and the
         Additional Allowance. Tenant shall be solely responsible for promptly
         paying (or reimbursing Landlord for) the remaining balance (if any) of
         all expenses of the Tenant Improvements which are in excess of $21.00
         per square foot (as to the original Premises) and $20.00 per square
         foot (as to the Additional Premises) and which are not to be
         incorporated into Base Rent pursuant to the provisions of subparagraph
         (b) above.

         IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment as
of the 8th day of February, 2001. Except as expressly modified herein, the terms
and conditions of the Lease remain in full force and effect.

LANDLORD:                                    TENANT:

LM VENTURE, LLC,                                      EMULEX CORPORATION,
a Delaware limited liability company                  a California corporation

By WGG LONGMONT DEVELOPMENT,
     LLC,

   a Colorado limited liability company,          By /s/ Sadie A. Herrera
   Manager                                           --------------------

   By /s/ Robert C. Goltermann
      ------------------------

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                                    EXHIBIT A

Depiction of Premises

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