File associations problem

[deeno ukf net]

Can someone help with this, I must be missing something pretty obivous,
but I've upgraded to Gnome 2.8 on fedora 2, and have now lost all my
file associations in Nautilus. Clicking on any file type results in
'Can't display location -> There was an error launching the
application.'

Also, the 'Open With' tab in the properties dialog just shows 'No
applications selected'. When I try to add a new association, nothing
gets added into the list, no matter how many times I try.

Any suggestions please....this is driving me crazy as my system is
pretty useless without this working.

Thanks.