I'm having difficulty with an old application I developed which used session handling to store data from page view to page view, depending on the action taken. It worked on the old server, my development machine, and my own host's server. I recently tried building a Mac OSX server and it didn't work on that, it also (more importantly) doesn't work on our new host's server. I'm at a loss as to why.

I've added a debug area below the content on these pages to watch what happens to the session during these errors on specific servers. At times, portions of the session will no longer exist. Using the browser's back button (re-rendering the original page that set the session) and clicking on the same link will restore the missing information which in fact existed prior to the previous page and was not modified in either of these pages (programmatically). On one action, I lose the $SESSION entirely. I would tend to think there's a problem with my code, but I've tested this on similarly built servers running the same version of PHP with the same session settings in php.ini...I now think there may be a software/hardware issue with sessions on different setups.

So...Are there any tools available to determine and/or examine the communication relay between the OS and the PHP engine?

I know this is a little off-kilter for the forum, but I think "other software development techniques" works here.