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                                                                   Exhibit 24.11

                                POWER OF ATTORNEY

STATE OF GEORGIA
COUNTY OF CHATHAM


         KNOW ALL MEN BY THESE PRESENTS that Michael N. Thompson, having an
address at 7 East Congress Street, Suite 500, Savannah, Georgia 31401, has made,
constituted and appointed and BY THESE PRESENTS, does make, constitute and
appoint Douglas Crocker II and Michael J. McHugh, or either of them, having an
address at Two North Riverside Plaza, Chicago, Illinois 60606, his true and
lawful Attorney-in-Fact for him and his name, place and stead to sign and
execute in any and all capacities this Annual Report on Form 10-K and any or all
amendments to this Annual Report granting unto each of such, Attorney-in-Fact,
full power and authority to do and perform each and every act and thing,
requisite and necessary to be done in and about the premises, as fully, to all
intents and purposes as he might or could do if personally present at the doing
thereof, with full power of substitution and revocation, hereby ratifying and
confirming all that each of such Attorney-in-Fact or his substitutes shall
lawfully do or cause to be done by virtue hereof.

         This Power of Attorney shall remain in full force and effect until
terminated by the undersigned through the instrumentality of a signed writing.

         IN WITNESS WHEREOF, Michael N. Thompson, has hereunto set his hand this
25th day of February, 2002.


                                                  /s/ Michael N. Thompson
                                                  -----------------------
                                                  Michael N. Thompson

         I, Cathy McDuffee Pulkinen, a Notary Public in and for said County in
the State of aforesaid, do hereby certify that Michael N. Thompson, personally
known to me to be the same person whose name is subscribed to the foregoing
instrument appeared before me this day in person and acknowledged that he signed
and delivered said instrument as his own free voluntary act for the uses and
purposes therein set forth.

         Given under my hand and notarial seal this 25th day of February, 2002.


                                                  /s/ Cathy McDuffee Pulkinen
                                                  ---------------------------
                                                       (Notary Public)


                           [SEAL]
My Commission Expires:___________________