I am using PHP.

I'm building a fully modular CMS, which is destined for the public. Some people might view this as a framework, but I intend to write a set of extensions for it, extensions that will make it a CMS :P

Because it's completely modular I have a problem figuring out how to load extensions.

Practically I need to get the list of active extensions, so I can load them inside my base class. I load them by reading some file headers, which contain a "dependency" field. That field decides the order in which I have to instantiate the objects.

The problem is that when the CMS starts I have no database interface, because that's an extension too, so I can't store the active extensions list in the database :)

You might ask how are extensions activated in the first place. Well - in the administration interface, which is an extension as well (obviously on first install of the CMS there will be some extensions active by default).

Could writing that list inside a text file be a solution? The problem is that a lot of hosts are not very nice with scripts when they write files. And since this CMS is public I might have a problem here?