Preprocessor Port Scan not working

[Joshua Brown <joshua.l.b () gmail com>]

Is there a way to make sure that the "preprocessor port scan"? (Yes, it is
enabled in the config.) It was tested by port scanning the server with snort
on it and it did not show a port scan from the scanning computer. It does
show port scans from other servers that need to be ignored but that is the
only port scanning it shows.

Any help would be much appreciated, thanks.
Joshua