Trying to compile php 5.0.3 on solaris 10 build 72 turned out to be not as smooth as expected. Apparently the config.guess script does not return the correct string.
In order for configure to work correctly I had to specify the build and host explicitly
Also, Zend/zend_strtod.c should be (the __i386__ define has been added)
#if defined(__sparc__) || defined(__ppc__) || defined(__i386__)
#define u_int32_t uint32_t