my wiper motor?

I had the same problem with my 02 punto (Mk2). But assume that the set up is the same on yours.
Remove the wiper arms them take off the plastic cover that runs across the car under the windscreen - held in place by a number of screws and pull down to release from under windscreen.
You can now easily remove the wiper motor and spindle assemblys for the whole wiper mechanism, just a few bolts and the electrical conection.
Drill a small hole - about 2mm - through the shaft as close to the end as possible, where the conecting arm falls off. Reconect the connecting arm, place a washer on the shaft and then fit a split pin to keep everything in place. Refit everything back in place. The whole operation took me about 30mins

Hal
March 2009