Extension Development

I am currently trying to do extension development when I get the time and this tends to happen when I am at work where I use PFF. With Firefox 1.5 you can place a file inside the extensions folder in the format of "@" and inside that file place the directory path to the extension files. (ie: E:\projects\helloworld) and when you start up FF it loads it. However PFF doesn't seem to do this like Firefox 1.5 does? Mainly this just helps with not having to create a new xpi file and reinstall the extension every time a change is made to the extension code, you just restart FF.

Is there a way to fix this or get around this?

Thanks for the help.

-Erik