Session Question

Hello everyone-- I've got a strange question for you all today. Let me give you a quick background as to what is going on. The company I work for uses PHP's session stored in files to access information etc. The problem is this; they now want to use Java to access these session files. The thing is that in the php part of the application I would pass my session id to the Java servlet and then the Java servlet would use that session id to open the file on the server and grab the information it needed to run. However, apparently the Java servlet doesn't have read write permissions to do this. Is there anyway to set the file properties for the session files in php? I know this is really insecure but the company won't listen to me or the other developers who are begging to use a database, they'd rather use the files (originally they wanted to put all the session info encrypted in the URL and we all laughed). Anyway, any help would be great and if you would like to add an argument for us to use a database PLEASE let me know what it is. :)