This is what i did.

phpdir> ./configure --with-mysql=/usr/local --with-gd=/usr/local --enable-track-vars --enable-bcmath --with-apache=../apache-1.3.6
phpdir> make
phpdir> make install
apachedir> ./configure --prefix=/usr/local/apache --activate-module=src/modules/php3/libphp3.a

Then configure says my build

/usr/local/lib/libgd.so: undefined reference to `png_read_info'
/usr/local/lib/libgd.so: undefined reference to `png_destroy_read_struct'

And lots of lines like the 2 above.

 + doing sanity check on compiler and options
** A test compilation with your Makefile configuration
** failed. This is most likely because your C compiler
** is not ANSI. Apache requires an ANSI C Compiler, such
** as gcc. The above error message from your compiler
** will also provide a clue.
 Aborting!

This is a line from the libphp3.module file:

LIBS=" -R/usr/local//lib/ -R/usr/local//lib/mysql/  -L/usr/local//lib/ -lg
d -lttf -L/usr/local//lib/mysql/ -lmysqlclient -Lmodules/php3 -L../modules/php3 
-L../../modules/php3 -lmodphp3                        -lpam -lm -lcrypt $LIBS"

If i add -lpng to the line it works like a charm.

Since I am a unix newbie I am very sorry if this problem was just because my stupidity.

Best Regards
Magnus Boden