Web server file perms || More than I can chew.....

Hey all. Got a problem with a site builder app I've spent three months developing. On my local machine (win2k pro, apache), no problems -- everything works just as designed. Today I began testing on the live server; i.e. my client's hosting company (linux, apache 1.3.27, php 4.3.1) -- that's when the trouble started. The site builder app builds static pages based on changes made by users in our online administration center. When I test out creating a new site section; i.e. triggering my make_file function(writes page content to new file) I receive the following error: Warning: fopen(/local_server_path/file_to_create.php) [function.fopen]: failed to create stream: Permission denied I've attempted to chmod(777) my testing directory via ftp client, which appears to work; however, when I fileperms($file_in_test_dir), I get chmod(644), so clearly I'm not the owner. Pardon my ignorance here, but I as yet know little about dir/file perms. Should I contact the host and have them give me sufficient permissions? Any help so much appreciated as I am completely handcuffed at the moment. Thanks, --Noah