It seems that the configure script looks in .so files only when testing for things like TIFFOpen and read_jpeg_header, giving an error, even though the libraries were reported found. 

the following:

       ln -s libtiff.so.3.5 libtiff.so

fixed the issue. Same had to be done with libjpeg.

my configure ended up being:

./configure --with-apxs=/home/httpd/bin/apxs --with-mysql=/usr/local/mysql --with-gd=../gd-1.8.4 --with-jpeg-dir --with-pgsql  --enable-calendar --with-swf=/usr/lib/swf --with-ttf --with-tiff-dir=/usr --with-pdflib=/usr/local --with-zlib-dir

something needs to be done to discover the standard installation locations of shared libraries and inform the configure script, or make it able to find things. I spend many hours just telling it where to look, after installing the standard distros of the libraries.