Converting from gcc-2.96 to gcc-3.2.2

Hello,
        I have developed a C++ application that uses the Standard Template
Library using gcc-2.96 on an x86 machine under RedHat Linux V7.2. When I
try to compile the application on an x86 machine under RedHat Linux V9.0
using gcc-3.2.2-5, I get an error saying
"stl.h No such file or directory". Stl.h does exist in
/usr/include/g++-3/. If I add /usr/include/g++-3 to the include search
path, the compiler finds stl.h, but generates a host of errors arising
out of the STL header files.
        Is there some flag that I need to set?
Thank you for your help.
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  John W. McClurkin, PhD.             | jwm@xxxxxxxxxxxxxxx
  Information Technology Specialist   | VOX:  301-496-9216
  Laboratory of Sensorimotor Research | FAX:  301-409-0511
  National Eye Institute, NIH         |
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