COM problem with Microsoft Word & passworded files

I'm trying to work on a search engine for my Intranet at work. It needs to be able to scan Microsoft Word & Excel documents so I'm planning on using the COM support in PHP + the Microsoft Word & Excel viewer program. At the moment I'm using Microsoft Word 2000 SR 2 to develop it however I've hit a small problem in that it is possible to password files and a number of the documents on the Intranet are. I don't know which ones and they can be sat anywhere so this causes a problem or two. When using the Documents->Open() method on a password protected document - PHP hangs. It just sits waiting and eventually times out. Could anyone more knowledgeable than I, shed some light on to how I can check whether a files passworded before loading it ? Many thanks David McCormack