jpeg and cache problems

Hi, I have PHP-4.2.2 installed on my Cobalt RAQ3 and am having difficulties getting the jpeg libraries to function. I have the following config.sh script ./configure \ --with-apxs=/usr/sbin/apxs \ --enable-wddx \ --enable-ftp \ --with-gd \ --with-jpeg-dir=/usr/lib \ --with-regex=system \ --enable-track-vars No errors but no jpeg functions, I want to try changing the path for -- with-jpeg-dir but after installation phpinfo() shows the old path, I have tried removing config.cache but I cannot seem to get a new config script to run. Any help to how I clear the config cache and/or installing jpeg libraries will be greatly appreciated. TIA Phil.