PHP 5.2.5 make failure gdImagePngCtxEx undeclared

I'm trying to make PHP 5.2.5 on AIX 5.3 and having a problem during make. I get the following when running make. /bin/sh /usr/local/php-5.2.5/libtool --silent --preserve-dup-deps --mode=compile /usr/local/php-5.2.5/meta_ccld -I/opt/freeware/include -Iext/gd/ -I/usr/local/php-5.2.5/ext/gd/ -DPHP_ATOM_INC -I/usr/local/php-5.2.5/include -I/usr/local/php-5.2.5/main -I/usr/local/php-5.2.5 -I/usr/local/WebServer/plugins/include -I/opt/freeware/include/libxml2 -I/opt/freeware/include -I/usr/local/php-5.2.5/ext/date/lib -I/opt/freeware/include/freetype2 -I/usr/local/mysql/include -I/usr/local/php-5.2.5/TSRM -I/usr/local/php-5.2.5/Zend -D_THREAD_SAFE -I/usr/include -g -O2 -pthread -DZTS -c /usr/local/php-5.2.5/ext/gd/gd.c -o ext/gd/gd.lo /usr/local/php-5.2.5/ext/gd/gd.c: In function 'zif_imagepng': /usr/local/php-5.2.5/ext/gd/gd.c:2977: error: 'gdImagePngCtxEx' undeclared (first use in this function) /usr/local/php-5.2.5/ext/gd/gd.c:2977: error: (Each undeclared identifier is reported only once /usr/local/php-5.2.5/ext/gd/gd.c:2977: error: for each function it appears in.) make: 1254-004 The error code from the last command is 1. This is the configure used. ./configure \ --with-nsapi=/usr/local/WebServer \ --with-openssl=/opt/freeware \ --with-mysql=/usr/local/mysql \ --enable-force-cgi-redirect \ --with-gettext \ --with-libxml-dir=/opt/freeware/lib \ --with-gd=/opt/freeware \ --enable-gd-native-ttf \ --with-jpeg-dir=/opt/freeware \ --with-png-dir=/opt/freeware \ --with-freetype-dir=/opt/freeware \ --with-zlib-dir=/opt/freeware Any thoughts on what to check? Thanks, Bart