Shortcuts issue

Hey,

small issue with the shortcuts window, basically I just wanted to add a 
shortcut to activate a .desktop file but somehow I messed it up, and now 
instead of just not working, the (now non-existant) .desktop file 
shortcut entry is permanent (there is no tiny trashcan delete button) 
and I cant do anything about it. It can't even be worked around using 
the reset or defaults button so I'm kinda stuck here.
Any help would be appreciated!

Thanks in advance,
Promitheas