PHP installation--gcc error

[songwind]

I tried to install PHP 5.1 in Red Hat Linux, when I did the following:
./configure --with-mysql

I got this message:

checking for gcc... no
checking for cc... no
configure: error: no acceptable cc found in $PATH

But the gcc should be installed in the system already, when I do "locate gcc", it showed me the following:
/usr/libexec/gcc
/usr/libexec/gcc/i386-redhat-linux
/usr/libexec/gcc/i386-redhat-linux/4.0.1
/usr/libexec/gcc/i386-redhat-linux/4.0.1/cc1
/usr/sbin/libgcc_post_upgrade
/usr/share/ghostscript/Resource/ac14/CMap/HKgccs-B5-H
/usr/share/ghostscript/Resource/ac14/CMap/HKgccs-B5-V
/usr/share/ghostscript/Resource/CMap/HKgccs-B5-H
/usr/share/ghostscript/Resource/CMap/HKgccs-B5-V
/usr/share/locale/de/LC_MESSAGES/msgcc
/usr/share/locale/es/LC_MESSAGES/msgcc
/usr/share/locale/it/LC_MESSAGES/msgcc
/usr/share/locale/fr/LC_MESSAGES/msgcc
/usr/share/locale/C/LC_MESSAGES/msgcc
/usr/share/locale/pt/LC_MESSAGES/msgcc
/usr/share/doc/libgcc-4.0.1
/usr/share/doc/libgcc-4.0.1/COPYING.LIB
/usr/lib/gcc-lib
/var/cache/yum/updates/packages/libgcc-4.0.1-4.fc4.i386.rpm
/var/cache/yum/updates/headers/libgcc-4.0.1-4.fc4.i386.hdr
/lib/libgcc_s.so.1
/lib/libgcc_s-4.0.1-20050727.so.1

Does it mean the system has gcc installed already? Sorry, I don't know where to look,
thanks.