libphp4.so not loading into apache (RH 7.3)

Hi, When I'm trying to load Apache with the PHP 4.2.3 module and start Apache I get the following error: Syntax error on line 236 of /usr/local/apache/conf/httpd.conf: Cannot load /usr/local/apache/libexec/libphp4.so into server: /usr/local/apache/libexec/libphp4.so: undefined symbol: gdImagePngCtx /usr/local/apache/bin/apachectl start: httpd could not be started An ldd on /usr/local/apache/libexec/libphp4.so gives me: libgcc_s.so.1 => /lib/libgcc_s.so.1 (0x40179000) libc.so.6 => /lib/i686/libc.so.6 (0x42000000) /lib/ld-linux.so.2 => /lib/ld-linux.so.2 (0x80000000) I've even tried upgrading to GCC 3.2 (since RH's gcc is known to have issues), but no luck yet. Thanks in advance, Leendert