I've been exploring converting aaf to xml for a project. I got the following error message:

Users\spearsc\Documents\Visual Studio 2008\Projects\AAF-src-1.1.6\AAF\AAFWinSDK\
vs9\Utilities\aaffmtconv\Release\aaffmtconv.exe" -xml Project.a
af Project.xml
Invalid extendible enumeration value encountered: urn:uuid:0c3bea40-fc05-11d2-8a
29-0050040ef7d2. The property (1e06, 'Category') will not be saved.

I'm trying to figure out what this error message means, and I cannot find anything online. I did notice that an xml file was created. Maybe I do not need to be worried about this?