I keep getting this message
10053 error, software caused connection abort

I recently moved back to college and this is the 3rd day I've been back and i haven't gotten that message until today. i got it 10 times in 2 hours and the last time i connected to mIRC it stayed connected for less than 5 min. when i was at home i didn't get the error message. My college doesn't block mIRC either.
sometimes i get another error message instead of the 10053 error message.
i have win xp. i have noticed that when i idle for more than an hour it disconnects me. Until now i have had no problems with mIRC.