Solaris 8 PHP 4.3.1 Install

I've been fighting through issues one by one on this install and have solved the majority of them, but I've come up against a wall. I'm configuring PHP solely to use with Snort, MySQL and Acid for analysis of Intrusion Detection events. When I compiled as a CGI module, everything worked fine. Acid requires that PHP be installed as an Apache module, so I added '--with-apxs2=/usr/local/apache/bin/apxs' to my configure line. Apache 2 is installed in /usr/local/apache. Here is my full configure statement: ./configure --with-mysql --enable-bcmath --with-gd --enable-sockets --with-a pxs2=/usr/local/apache/bin/apxs --with-zlib-dir=/usr/local/lib Now the configure works, but the compilation fails with this error: /bin/sh libtool --silent --mode=compile gcc -Imain/ -I/export/home/jdthomas/install/php-4.3.1/main/ -DPHP_ATOM_INC -I/export/home/jdthomas/install/php-4.3.1/include -I/export/home/jdthomas/in stall/php-4.3.1/main -I/export/home/jdthomas/install/php-4.3.1 -I/usr/local/ apache/include -I/export/home/jdthomas/install/php-4.3.1/Zend -I/usr/local/i nclude -I/export/home/jdthomas/install/php-4.3.1/ext/xml/expat -D_POSIX_PTH READ_SEMANTICS -I/export/home/jdthomas/install/php-4.3.1/TSRM -g -O2 -pref er-pic -c main/internal_functions.c -o main/internal_functions.lo main/internal_functions.c:1: parse error before `.' In file included from /usr/include/stdio.h:22, from /export/home/jdthomas/install/php-4.3.1/Zend/zend.h:35, from main/php.h:34, from main/internal_functions.c:24: /usr/include/iso/stdio_iso.h:186: parse error before `__va_list' /usr/include/iso/stdio_iso.h:187: parse error before `__va_list' /usr/include/iso/stdio_iso.h:188: parse error before `__va_list' In file included from /export/home/jdthomas/install/php-4.3.1/Zend/zend.h:35, from main/php.h:34, from main/internal_functions.c:24: /usr/include/stdio.h:227: parse error before `__va_list' In file included from main/php_syslog.h:14, from /export/home/jdthomas/install/php-4.3.1/ext/standard/php_ext_syslog.h:26, from /export/home/jdthomas/install/php-4.3.1/ext/standard/php_standard.h:34, from main/internal_functions.c:49: /usr/include/syslog.h:28: parse error before `__va_list' make: *** [main/internal_functions.lo] Error 1 Can someone tell me what I'm doing wrong?