I can't find the thread unfortunatley, but I came across someone recalling using abrosia at a university and having their main and side accounts getting frozen, but the other people they knew that played neopets didn't have their acounts frozen.
This other thread says some of the same things:
http://www.neocodex....on-about-proxy/
So, in this case I'd guess it'd be safe to use multiple accounts at a university as long as care is taken. Use different computers if possible.