auto user deleting?

as discussed in here:
http://vbulletin.com/forum/showthread.php?threadid=5640
It will really help me/

First, it has been asked many times not to use brackets in your subject unless it is a hack release.

Second, what is the point of posting topics that are simply links to other posts?

Third, What is your question?

~Chris

:( sorry. didnt really knew its wrong. anyway the question is how can I do that uesrs that didnt post after a month from registering are auto-deleted?