Recycle Bin doesn't erase files

Hi there guys!

i'm having a problem here.... since yesterday i cannot empty my Recycle Bin
.... the files i delete are moved there, but, when i right-click to "empty
recycle bin" .. it simply does nothing... and the SHIFT+DEL shortcut also
isn't working anymore ...

'til earlier i could empty the recycle bin by selecting the files that where
inside it and then deleting it again.. but it also isn't working anymore ....

i'm using Vista Ultimate... and i don't use a "restore point" ... anyone
knows how to solve this? or already had this problem?

thx in advance...