How to compile 64 bit apache modules on CentOS?

I've tried to install mod_passenger on a 64 bit CentOS5.3 machine and the module compiles into a 32 bit .so file. Followed standard recipe: gem install passenger; passenger-install-apache2-module.

• apache 2.2.3
• Rails 2.3.5
• gem 1.35

The passenger-install-apache2-module command emits a script (while running it) with lot's of flags like -m32 and -march=i386. I've captured the script, replaced -m32 with -m64 and -march=i386 with -march=x86_64, re-ran it (with some extra include path and APXS2 variables) but the output object is still in 32 bit format.

Could someone share insight on how to force the 64-bitness upon the passenger?

edit: later I found out that any module I would try to compile would be built into a 32 bit version, so it's not specific to passenger

Thanks!