Try this telnet in become root and open up his mail file pine -f /home/spool/mail/username Then delete away as long as he wants you too.
Pine is just an email client, correct? If so, the files are the same for Pine or any other email client - if you have openwebmail installed, it is a nice GUI way to do what you need to do, that's what we've been doing. The nice thing is that the email file gets repacked after you have deleted messages, and the key to making the file smaller.
If you don't have the user's password, check out my mean-thread the other day on how to take care of it, but basically - again, this is assuming you have openwebmail or equivalent installed (and maybe Pine can do the repack as well, not sure, too ugly) - copy the usermail (in home/spool/mail) to a dummy account, use the mail software to get rid of what you need to, copy the file back. The user will never even know you did this.
Jale