361738 php script to handle file perm

I currently have a number of PHP scripts that use web-based file uploading, which means the destination directory has to have a permissions value of 777. I'd like to see if there is a way to structure my scripts such that the directory can maintain a permission of 755 and then when the script runs (on the fly) it changes the directory to 777 and then back to 755 when the upload task is complete. If that also means changing the ownership structure of the directories on the server itself I can do that, I own the servers these scripts run on. I'd just have to be told what to do on the server so that this idea will work when I install these PHP scripts on other accounts. I use both FCKeditor's file browser and a Dreamweaver extension that creates upload fields if that helps. The server is a Unix running CentOS 5. You won't get shell access with this project, I can provide sample files for the DW extension and the FCKeditor file browser if needed although it's pretty much a plain vanilla version of the file browser files...no customizations on my end.