[Fedora-packaging] gnome/nautilus filetype detection and default opening application

Hi, Basically, my package (pyvnc2swf) creates shockwave flash files with an extension of .swf. Nautilus detects the file as Shockwave flash file, and sets the default handler to gnash. 1. gnash crashes on at least some pyvnc2swf created swf files, yet it is the default for this file extension (at least on my system). 2. pyvnc2swf includes a limited .swf player that is able to only play files created by pyvnc2swf. Previously I added a .desktop file for vnc2swf-play, which causes nautilus to show pyvnc2swf-play as a possible player of swf files. However, it can't play all swf files. I was hoping to improve upon this by creating a subtype: glob "*.vnc2.swf", and change the package to output files with this "pre" extension, and then "tell" nautilus about that extension, so that: 1. pyvnc2swf files are automatically opened by vnc2swf-play 2. normal swf files are opened by any other swf player Is the way to do this as described at: http://people.gnome.org/~shaunm/admin-guide/mimetypes-9.html correct for f12/f13/devel ? Or do you have better ideas on how to achieve the above ?