The suspension reason says it all. You installed and attempted to use a prank email script which forges email headers - under the AUP this is considered malicious and is not tolerated.
The spoofing of headers in emails, even for "joke" purposes, is one of several reasons an email provider will outright block us. We're already blocked by hotmail, and as such we've taken a much more firm stance on "pranks" such as this one. You will not be unsuspended, as your actions put the accessibility of other users accounts at risk.