Bug#251376: How to change 'abiword' as XML viewer back to 'yelp'

[Alfie Costa]

Found a way to change 'abiword' as XML viewer back to 'yelp'.

 From the Gnome Start menu, (its button looks like a footprint on my 
task bar), click:
'Applications>Desktop Preferences>Advanced>File Types and Programs'

A 'File Types and Programs' box pops up with a list of file type categories:

	Audio
	Documents
	Images
	...etc.

Hilite 'Documents>Extended Markup Language (XML)>XML document   .xml', 
then click the 'Edit' button.  An 'Edit file type' box pops up, near the 
bottom of which are two fields:

1	'Default action' (mine said 'custom')
2	'Program to run' (mine said 'abiword')

Change the 2nd field to 'yelp', then click 'OK'; close the 'File Types 
and Programs' box.  Now 'yelp' (not 'abiword') shows XML again.

That doesn't fix this bug though, it only treats the symptom.   How were 
'abiword' or 'gvim' set as .xml defaults?  I didn't change nuthin, and 
'yelp' worked OK before the upgrade.