How to link .so lib into a PHP Extension

Hello, I am creating an extension to handle HASH encrytions for the HSBC Cardholder Payment Interface. Right now the recommended way of doing it is to drop to an exec to get the hash. I simply found this not very elegant and decided to try and create an extension. I found a 2 part (3rd part to come it seems) tutorial on Zend that has helped quite a bit. But I am coming up with a small linking issue I believe. Basically everything compiles, but when I move the extension .so file into my php extension dir and restart apache, I get the error message that it was unable to load the module due to unrecognized symbols. So basically it does not know to look for them in /usr/lib/libCcCpiTools.so. Would this be something I need to add to config.m4? If so, can someone tell me what I need to add? Thanks, Mike