problem double-clicking shell scripts

[Donkergroen bvba]

I wrote a few shell scripts that do some stuff for me , that I keep  
in the finder sidebar.
All off a sudden clicking them no longer works. I get the popup :  
"There is no default
application specified to open the document "testScript"

The script also lost its icon in the finder. ( the little terminal  
with exec )
All commands in /usr/bin also lost this icon. ( except for links in / 
usr/bin )
This is the same for another user.

The only thing I have been doing is installing some software with the  
darwin port command.

I have no idea how to fix this. ( googling didn't help )

Any ideas where to look ?

Dirk