If you use v6.1x then you can use
http://www.erler.org/Olathe/exploit%20fix.mrc which will stop you from being crashed as well as globally banning the user from all channels you are in, but it won't work for v6.0x and theres no way that i know of, of storing the text frem a dcc send anywhere before its takes affect. I tried using on ctcp, but it will crash mirc before the on ctcp can be triggered. The above script catches it at debug level before mirc does something with it, which is why it works.
