Unwanted, huge messages

[Vittorio]

I use mutt with fetchmail to get loads of messages from the many lists
I'm subscribed to.

Now sometimes it happens that very long (say, exceeding 1,000,000
octets), unwanted messages slow down the download of 'wanted' messages.

My question is:

When using fetchmail how can I delete messages greater than a certain
size (say 100,000 octets) directly on the POP3 server avoiding that
slowdown?

Ciao
Vittorio