i'm attempting to recompile php after upgrading gd on my system from 1.8.x to 2.0.x.

i get the following when i attempt to recompile:
In file included from gd.c:83:
gd_ctx.c: In function `_php_image_output_ctx':
gd_ctx.c:70: structure has no member named `free'
gd_ctx.c:98: structure has no member named `free'
gd.c: In function `_php_image_type':
gd.c:1014: structure has no member named `free'
gd.c:1017: structure has no member named `free'
gd.c: In function `_php_image_create_from':
gd.c:1209: structure has no member named `free'
make[3]: *** [gd.lo] Error 1
make[3]: Leaving directory `/var/installed/php-4.2.3/ext/gd'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/var/installed/php-4.2.3/ext/gd'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/var/installed/php-4.2.3/ext'
make: *** [all-recursive] Error 1

any idea what's causing this problem? i'm getting rather frustrated...