it is not possible for Power Messenger to know if the email is going to a Spam Folder, that happens on the client end, and cannot be tracked by the server.
There is a spam reporting servicer that will evaluate the email message and return results showing the probability of an email message being treated as spam. The original service that we where using has changed to be a paid service though.
See this thread for details on how you can change the spam reporting service to a different free one.
showthread.php?t=21175