PHP compilation error under Solaris

I am trying to compile php-4.0.6 on Solaris, in a sun sparc machine. I have the latest gcc, bison 1.28, gnu tar, and everything php seems to require. My gcc resides in a remote partition, but it works fine (I've compiled Apache and MySQL). Does anyone know what does this error message means? > # make > Making all in Zend > make[1]: Entering directory `/opt/src/php4/Zend' > /bin/sh ../libtool --silent --mode=compile gcc -DHAVE_CONFIG_H -I. -I. -I../main > -D_POSIX_PTHREAD_SEMANTICS -DSUPPORT_UTF8 -DXML_BYTE_ORDER=21 -o2 -I/opt/local/openssl/include -c > zend_language_scanner.c > In file included from ../main/php_config.h:1919, > from zend_config.h:1, > from zend.h:44, > from zend_language_scanner.c:2719: > /usr/include/stdlib.h:165: conflicting types for `getsubopt' > /usr/include/stdio.h:267: previous declaration of `getsubopt' > /usr/include/stdlib.h:189: conflicting types for `getopt' > /usr/include/stdio.h:265: previous declaration of `getopt' > In file included from /usr/include/string.h:18, > from ../main/php_config.h:1931, > from zend_config.h:1, > from zend.h:44, > from zend_language_scanner.c:2719: > /usr/include/iso/string_iso.h:60: warning: conflicting types for built-in function > `memcmp' > /usr/include/iso/string_iso.h:61: warning: conflicting types for built-in function > `memcpy' > /usr/include/iso/string_iso.h:65: warning: conflicting types for built-in function > `strcmp' > /usr/include/iso/string_iso.h:66: warning: conflicting types for built-in function > `strcpy' > In file included from zend_language_scanner.c:2749: > /usr/include/unistd.h:382: conflicting types for `rename' > /usr/include/iso/stdio_iso.h:165: previous declaration of `rename' > zend_language_scanner.c:5441: conflicting types for `zend_scan_string' > zend_language_scanner.c:256: previous declaration of `zend_scan_string' > zend_language_scanner.c:5459: conflicting types for `zend_scan_bytes' > zend_language_scanner.c:257: previous declaration of `zend_scan_bytes' > zend_language_scanner.c:5552: conflicting types for `yy_fatal_error' > zend_language_scanner.c:293: previous declaration of `yy_fatal_error' > make[1]: *** [zend_language_scanner.lo] Error 1 > make[1]: Leaving directory `/opt/src/php4/Zend' > make: *** [all-recursive] Error 1 >