I guess, it is a problem with x86_64 ...
wrong CXX flags ?
EDIT : Like NeddySeagoon said, when I was writing the post !
Have a look in 'gdal.spec' from gdal-1.5.1-5.fc9.src
( The spec file is attached as gdal.spec.txt ).
Also please Google .. gdal cxxflags ..
There may be some suggestions.
Compiles with no errors on an x86 Fedora 9.