[otrs] Blacklisting addresses?

All With apologies to the list is this has been covered before... I am in a situation where I need to blacklist mail originating from a particular address. This address can communicate normally with other users, but just needs blacklisting from otrs. I can think of using either procmail or hacking the code as a solution, however, I am not sure which is the preferable way. Note that hacking the code would be done in such as way as to read from a blacklist rather than just hardcoding the address. My question is: Have any folks out there had to do this, if so - how and what was your experiences from it (i.e. was it reliable, was it maintainable) etc. Kind regards Chris Mellor