Where is gdlib.so for PHP?

[Michael J. Pawlowsky]

If I look at phpinfo() I see that gd was compiled as an extension. 
However I do not have a libgd.so in /usr/lib/php4.
I grabbed the source for PHP and tried to do a rpmbuild of it.

First problem I hit was that it choke when trying to look for curl.
I don't really need it so I just commented it out in the configure of 
php.spec (but if someone knows why, I would like to figure it out).
Now I can compile it, but it doesn't seem to build libgd.so.
Does anyone know what I need to do to get it?

Thanks,
Mike