Appendix B.1	PerlMX

http://www.ActiveState.com/Products/PerlMx/ 
ActiveState releases PerlMx 1.0  

PerlMx is a mail filter engine designed to operate under sendmail. 
Beginning with v8.10, sendmail provides scriptable hooks into all 
stages of an e-mail transaction, allowing custom actions on any 
aspect of the transaction, including the content of the message 
itself. PerlMx allows these hooks to be written in Perl, making for 
rapid prototyping, debugging, and deployment of custom e-mail 
filtering solutions.