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            FIRST AMENDMENT TO THE LEASE BETWEEN CREDIT SUISSE FIRST
             BOSTON CORPORATION (CSFB) ("TENANT") AND TM PARK AVENUE
                           ASSOCIATES LP ("LANDLORD")
                       DATED AUGUST 16, 2000 (THE "LEASE")

     WHEREAS, Landlord and Tenant entered into the Lease dated as of August 16,
2000, which Landlord and Tenant desire to amend as of December 8, 2000.

     THE LEASE IS HEREBY AMENDED AS FOLLOWS:

     1.   Article 1 of the Lease is hereby deleted and in its place is
          substituted the following:

          SECTION 1.01. Landlord leases to Tenant, and Tenant hires from
Landlord, and upon and subject to the covenants, agreements, Terms, provisions
and conditions of this Lease, for the Term hereinafter stated, that portion of
the twenty-story building (hereinafter called the "Building") known as 315 Park
Avenue South, New York, New York, (hereinafter called the "Building") consisting
of the entire Second, Third, Fourth, Fifth, Sixth, Seventh, Eighth, Twelfth,
Thirteenth, Fourteenth and Fifteenth Floors, portions of the Lobby Floor (the
"Tenant's Lobby") as set forth on the diagram marked Exhibit A attached hereto
and a portion of the Basement Floor as set forth on the diagram marked Exhibit
A-1 attached hereto (except for common areas, including, without limitation,
areas devoted to elevator shafts and conduits for mechanical systems, which
common areas Tenant shall have non-exclusive right to use with other Building
occupants but excluding Tenant's dedicated shaft space. Such leased Premises,
together with all fixtures, equipment, installations and appurtenances which at
the commencement of or during the Term of this Lease are thereto attached
(except items not deemed to be included therein and removable by Tenant as
provided in Article 4 of this Lease) are hereinafter called the "Premises". The
plot of land on which the Building is erected is hereinafter called the "Land".
This agreement is called this "Lease".

          SECTION 1.02. (a) The Commencement Dates of the respective floors of
the Premises are as follows:

<Table>
<Caption>
     FLOORS                                      COMMENCEMENT DATE
<S>                                              <C>
     3, 5, 6, 7, 12, 13, 14, 15                  September 1, 2000
     4                                           September 18, 2000
     8                                           October 2, 2000
     2                                           October 12, 2000
     Portion of Lobby (4,010 sq. ft.)            October 16, 2000
     Portion of Lobby (9,121 sq. ft.)            December 8, 2000
     Portion of Basement (11,038 sq. ft.)        December 8, 2000
</Table>

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Whenever the phrase "Commencement Date" appears in the Lease it shall refer to
the respective dates set forth above in this Section. This Lease has commenced
on the dates set forth above (the "Commencement Date") and shall expire unless
same shall sooner cease or be terminated as hereinafter provided or pursuant to
law on April 30, 2017 (such term being hereinafter referred to as the "Term").

     (b) The 9,121 square foot portion of the Lobby and the 11,038 square foot
portion of the Basement shall be collectively referred to as the "New Space".

          SECTION 1.03. The rent reserved under this Lease for the Term shall be
a fixed annual rent (hereinafter called the "Fixed Rent") as follows:

          (a) At the annual rate of $9,353,502 per annum for the period from and
including the Commencement Date to and including September 30, 2005 and at such
rate to be paid in equal monthly installments of $779,458.50 each, in advance,
on the last day of each and every prior calendar month during the entirety of
such period (plus such Additional Rent and other charges as shall become due and
payable hereunder) by Federal Funds wire transfer, to an account designated in
writing by Landlord;

          (b) At the annual rate of $10,166,850 per annum for the period from
and including October 1, 2005 to and including September 30, 2010 and at such
rate to be paid in equal monthly installments of $847,237.50 each, in advance,
on the last day of each and every prior calendar month during the entirety of
such period (plus such Additional Rent and other charges as shall become due and
payable hereunder), by Federal Funds wire transfer, to an account designated in
writing by Landlord;

          (c) At the annual rate of $10,980,198 per annum for the period from
and including October 1, 2010 to and including September 30, 2015 and at such
rate to be paid in equal monthly installments of $915,016,50 each, in advance,
on the last day of each and every prior calendar month during the entirety of
such period (plus such Additional Rent and other charges as shall become due and
payable hereunder) by Federal Funds wire transfer, to an account designated in
writing by Landlord; and

          (d) At the annual rent of $ 11,183,535 per annum for the period from
and including October 1, 2015 to and including April 30, 2017 and at such rate
to be paid in equal monthly installments of $ 931,961.25 each in advance on the
last day of each and every prior calendar month during the entirety of such
period (plus Additional Rent and other charges as shall become due and payable
hereunder) to an account designated in writing by Landlord.

          SECTION 1.04. Tenant agrees promptly to pay the Fixed Rent, Additional
Rent and other charges herein reserved as and when the same shall become due and
payable, without demand thereof, and without any set-off or deduction whatsoever
except as expressly provided in this Lease and to keep, observe and perform, and
to permit no violation of, each and every of the covenants, agreements, terms,
provisions and conditions herein contained on the part and on behalf of Tenant
to be kept, observed and performed. Any Fixed Rent payments that are due under
this Lease shall, if not received by Landlord by

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the fifth day after such rent is due, bear a three (3%) percent surcharge for
the late payment and interest at the Default Rate; provided, however, that if a
monthly payment is inadvertently late no more than once in any twelve month
period and is paid within two (2) days after notice from Landlord to Tenant, the
three (3%) percent surcharge shall not apply to that late payment.

          SECTION 1.05. Additional Rent shall mean all charges owed pursuant to
Sections 16.04, 19.01, 21.02, 21.03, 21.04, 22.06, 23.02, 23.03 and 23.04 and
such other Sections of similar purport.

          SECTION 1.06. If, by reason of any of the provisions of this Lease,
the Term expires on any date other than the last day of a calendar month (except
if the Term Terminates by reason of Tenant's default hereunder), the Fixed Rent
and Additional Rent for such calendar month shall be equitably prorated. If the
Commencement Date of the respective floors of the Premises of this Lease are on
any day other than the first of a calendar month, the Fixed and Additional Rent
for those floors shall be prorated for that first month.

          SECTION 1.07. For all purposes hereof, it is agreed that the Premises
consists of 203,337 square feet consisting of 16,288 square feet on each of the
second through eighth floors and the twelfth through fifteenth floors and 13,131
square feet in the Tenant's Lobby and 11,038 square feet in the Basement.

          SECTION 1.08. Notwithstanding any other provisions of the Lease,
Tenant will not be obligated to make any payments of the Fixed Rent for: (a) the
two month period commencing with the Commencement Date of the applicable floors
and (b) the month of September, 2003. During the months of October 1, 2005
through September 30, 2006, Tenant shall receive a rent credit of $63,603.47 per
month (or, if Tenant shall have expended less than $483,179 in order to remove
the linoleum or other floor tiles in the Premises, and if all such linoleum or
other floor tiles have not been removed, the credit will be reduced by one
twelfth (1/12) of $483,179 less the amount so expended). Tenant shall pay, upon
the execution of this Lease, the Fixed Rent for the third month after the
Commencement Date, in respect to each applicable floor. Tenant shall pay, upon
the execution of this First Amendment, the sum of $77,276.16, which represents
the Fixed Rent for the month of February 2001 for the New Space.

     2.   Section 3.01 is hereby amended by adding the following sentence to the
          end of the Section: "Notwithstanding anything above to the contrary,
          Tenant may use (i) the Basement only for storage and the placement of
          mechanical equipment; and (ii) Tenant may use the Tenant's Lobby for a
          conference facility and other purposes ancillary to its office use".

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     3.   Section 3.05 is hereby amended as follows:
          The last sentence is deleted and replaced with "Tenant may place such
          exterior signage on the exterior of the First Floor of the Building as
          Landlord in its reasonable discretion shall allow. Tenant shall
          maintain and repair the windows on the exterior of the Tenant's Lobby.
          Except as provided in the Lease, Landlord will not allow any exterior
          signage on the Building's North and West facades."

     4.   Section 3.06 is hereby amended as follows:
          The last sentence of the Section is deleted and in its place shall
          appear the following:
               "The Park Avenue elevators shall be re-programmed, as soon as is
          practical, so that when each specific elevator is turned over to
          Tenant it shall be able to service all floors of the Building. The
          cost of the re-programming will be borne by the Tenant. One half of
          this cost (not to exceed $350,000) shall be returned to the Tenant in
          the form of a rent credit to be applied in sixty (60) equal monthly
          installments starting in November 2005 and ending in October 2010. In
          computing the amount of the credit, the cost will be increased by
          applying a Six and a half (6.5%) percent annual interest factor. The
          two most westerly of the Park Avenue elevators shall be dedicated
          exclusively for Tenant's use (the cost of providing the openings on
          each floor shall be totally borne by the Tenant). When the Tenant
          leases fourteen (14) floors in the Building, Landlord shall dedicated
          a third elevator for Tenant's exclusive use. The other elevators will
          only open on the floors the Tenant does not occupy. For the purpose of
          determining when Tenant is entitled to receive additional dedicated
          elevators, neither the Tenant's Lobby nor the Basement shall
          constitute floors. The Landlord reserves the right at all times to use
          all of the Park Avenue elevators that open on the Basement floors to
          obtain access to the Basement."

     5.   Section 16.03 is amended by adding the following sentences at the end
          of the Section: "Tenant has decided to install supplemental air
          conditioning units throughout the Premises and to install two cold air
          drying units on the roof at its own cost and expense Landlord shall
          have no responsibility to repair or maintain such supplemental units
          or systems. Tenant shall have reasonable right of access to the roof
          for purposes of maintenance and repair of such equipment.

     6.   Section 21.04 of the Lease shall be amended by deleting the amount
          $41,978.29 in line 3 of the Section and replacing it with the amount
          $46,598.06.

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     7.   Section 22.04(g) shall be amended by adding the following sentence:
          "Tenant may only sublet or assign the Basement and Lobby Floor in
          conjunction with a sublease or assignment of the Tenant's entire
          Premises."

     8.   Section 23.01(d) shall be amended by deleting the words fifty-six
          percent (56%) and replacing it with "62.163%".

     9.   Section 23.01(h) is amended by deleting the "215,444 square feet" in
          lines 3 and 5 and substituting "203,337 square feet"; furthermore, in
          line 5 the amount $107,722 is deleted and replaced with $101,668.50.

     10.  As to the New Space, Section 27.06 is amended to delete "Insignia ESG
          and Company" and to substitute in instead "CSFB Realty Services".

     11.  Section 27.28 of the Lease is hereby deleted.

     12.  In regard to the New Space the following Sections of the Lease shall
          not apply:

               a. Section 7.01 as to the Basement
               b. Section 7.02
               c. Section 16.01 as it relates to the heating ventilation air
                  conditioning system.
               d. Section 16.03
               e. Exhibit C and Exhibit F.
               f. Landlord shall have no obligation to create demising walls in
                  the Lobby floor for Tenant.

     13.  Except as expressly set forth above, the Lease is unamended, unchanged
          and in full force and effect in regard to all of its terms.

                                        LANDLORD:
                                        TM PARK AVENUE ASSOCIATES LP

                                        By: /s/ Steve Mullins
                                           -----------------------------------
                                               NAME: STEVE MULLINS
                                               TITLE: GENERAL PARTNER

                                        TENANT:
                                        CREDIT SUISSE FIRST BOSTON CORPORATION

                                        By:
                                            --------------------------------
                                            NAME:
                                            TITLE:

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State of New York  )
County of New York ) ss.:

On the 26 day of December in the year 2000 before me, the undersigned,
personally appeared George Twill, personally known to me a Notary Public of
the Sate of New York or proved to me on the basis of satisfactory evidence to
be the individual(s) whose name(s) is (are) subscribed to the within
instrument and acknowledged to me that he/she/they executed the same in
his/her/their capacity(ies), and that by his/her/their signature(s) on the
instrument, the individual(s), or the person upon behalf of which the
individual(s) acted, executed the instrument.

/s/ [ILLEGIBLE]
-----------------------------
                                                            [SEAL ILLEGIBLE]

State of New York  )
County of New York ) ss.:

On the _______ day of December in the Year 2000 before me, a Notary Public in
the State of New York, the undersigned, personally appeared
_________________________, personally known to me a Notary Public of the State
of New York or proved to me on the basis of satisfactory evidence to be the
individual(s) whose name(s) is (are) subscribed to the within instrument and
acknowledged to me that he/she/they executed the same in his/her/their
capacity(ies), and that by his/her/their signature(s) on the instrument, the
individual(s), or the person upon behalf of which the individual(s) acted,
executed the instrument.

-----------------------------

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     7.   Section 22.04(g) shall be amended by adding the following sentence:
          "Tenant may only sublet or assign the Basement and Lobby Floor in
          conjunction with a sublease or assignment of the Tenant's entire
          Premises."

     8.   Section 23.01(d) shall be amended by deleting the words fifty-six
          percent (56%) and replacing it with "62.163%".

     9.   Section 23.01(h) is amended by deleting the "215,444 square feet" in
          lines 3 and 5 and substituting "203,337 square feet"; furthermore, in
          line 5 the amount $107,722 is deleted and replaced with $101,668.50.

     10.  As to the New Space, Section 27.06 is amended to delete "Insignia ESG
          and Company" and to substitute in instead "CSFB Realty Services".

     11.  Section 27.28 of the Lease is hereby deleted.

     12.  In regard to the New Space the following Sections of the Lease shall
          not apply:

               a. Section 7.01 as to the Basement
               b. Section 7.02
               c. Section 16.01 as it relates to the heating ventilation air
                  conditioning system.
               d. Section 16.03
               e. Exhibit C and Exhibit F.
               f. Landlord shall have no obligation to create demising walls in
                  the Lobby floor for Tenant.

     13.  Except as expressly set forth above, the Lease is unamended, unchanged
          and in full force and effect in regard to all of its terms.

                                        LANDLORD:
                                        TMPARK AVENUE ASSOCIATES LP

                                        By: /s/ Steve Mullins
                                            -------------------------------
                                            NAME: STEVE MULLINS
                                            TITLE: GENERAL PARTNER

                                        TENANT:
                                        CREDIT SUISSE FIRST BOSTON CORPORATION

                                        By:
                                            --------------------------------
                                            NAME:
                                            TITLE:

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State of New York  )
County of New York ) ss.:

On the 27 day of December in the year 2000 before me, the undersigned,
personally appeared Stephen Mullins, personally known to me a Notary Public of
the Sate of New York or proved to me on the basis of satisfactory evidence to be
the individual(s) whose name(s) is (are) subscribed to the within instrument and
acknowledged to me that he/she/they executed the same in his/her/their
capacity(ies), and that by his/her/their signature(s) on the instrument, the
individual(s), or the person upon behalf of which the individual(s) acted,
executed the instrument.

/s/ Maria Vullis                [SEAL]
-----------------------------

State of New York  )
County of New York ) ss.:

On the______ day of December in the Year 2000 before me, a Notary Public in the
State of New York, the undersigned, personally appeared _____________________,
personally known to me a Notary Public of the State of New York or proved to me
on the basis of satisfactory evidence to be the individual(s) whose name(s) is
(are) subscribed to the within instrument and acknowledged to me that
he/she/they executed the same in his/her/their capacity(ies), and that by
his/her/their signature(s) on the instrument, the individual(s), or the person
upon behalf of which the individual(s) acted, executed the instrument.

-----------------------------