double posting - repeating events

We have some events that occur repeatedly, each month.  Trying to put these on the calendar....the detection of double posting is very picky!   Is there a way to do repeated events?  Content and title of the event is basically the same each time, but the date varies each month.

Update - modified new_post.asp line 658 as follows:

'Modified to allow posting of repeat events  This mod should be reverted to prevent spam flood.  Need to look 'into having a boolean switch somewhere that allows multiple calendar postings for repeat events.
'Original code:
'    If (rsCommon("Message")    = strMessage) Then
'Modified code:
     If ((rsCommon("Message") = strMessage) and (dtmEventDate = "")) Then

This mod allows multiple sequential posts if they are calendar events.  So when I (or another authorized member) have to load such a series of events, I will switch the comment character from the second IF line to the first IF line in the text above, and save it (the way its shown above).  Then I make my multiple event posts, then switch the comment characters back to reinstate the spam/multiple post prevention.