1. A method for inhibiting or suppressing delivery of undesirable email messages through vulnerable systems comprising: (a) emulating one or more vulnerable systems that can be used by spammers to relay, forward or otherwise send undesirable email messages to target systems; and (b) automatically identifying, as being undesirable, email messages that are to be relayed, forwarded or otherwise sent to target systems via at least one of the one or more vulnerable systems being emulated at step (a).