Hey Paul, that depends on your location and e-comm laws. Most ISPs dont take kindly to mail bombing, especially when server resources drop, and will most likely nuke your account with them.
Shut off your IMAP functions and ban the mail() function in your php.ini
Most responsible ISP's have limits to the number of emails you can "spam" at once, so if they didn\'t block it, I wouldn't worry to much, unless someone\'s out to get ya'all already 😉