Automated Downloads WAS File Retrieval, unusual

After further research I have found that the JAVA problem is non-existant, so here is what I am left with: On a remote https server; 1. Access the login page with 3 pieces of information to be passed. Unfortunately this information cannot be passed via URL. 2. Activate login which creates a session id (JSP pages) 3. Retrieve list of files from a page to compare against files already downloaded (no problem here) 4. Retrieve files via download (zip format). I believe I can accomplish this with fopen or fsockopen. I hope to do this via a stand alone PHP executable called by a CRON on a daily basis. Any ideas for passing the three variables to the login page and activating the login? Thanks! Jay