Php extensions - linking to external libraries

Help Anyone out there know where and how I should sepecify external libraries to link to ? At the moment I have a line in my config.m4 which looks like : EXTRA_LIBS="$EXTRA_LIBS -lwebprodssinterface -llibrcgateway -llibplaylist" but whenever I build I get an error : /usr/bin/ld: cannot open -lwebprodssinterface I have LDPATH and LD_LIBRARY_PATH set to the directory containing these libraries. Anyone know how to specify the link directories and files in the php build system ? Cheers Larry ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Imerge Limited Tel :- +44 (0)1954 783600 Unit 6 Bar Hill Business Park Fax :- +44 (0)1954 783601 Saxon Way Web :- http://www.imerge.co.uk Bar Hill Cambridge CB3 8SL United Kingdom ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~