Dreamweaver and PHP includes

[cleverhandle]

I'm sure this is a simple problem, but I'm not sure where to start searching for it. I sometimes use Dreamweaver (MX, non-2004) to edit pages on a site that uses PHP, mostly just includes at this point. The problem: if I open one of my .inc files for editing, the toolbar with all the handy buttons deactivates. Presumably, DW doesn't know that the files are going to included into an html document and thus turns off the toolbar because it doesn't know what kind of code to use. Is there some way to give it a hint so that the toolbar works?