GFI SPAM filter blocking internal users email. Sending internal email to Outlook junk mail folder.

Hello all,
Background info:
New install of GFI mail essentials for Exchange on SBS 2003(Used older version on SBS 2000 without fault for 3 years).

Problem Description:
Some internal email goes to users Outlook(2003 & 2007) "junk mail" folders.
Domains are listed in General options correctly. No internal domain is listed. All filters set to send SPAM to users "junk mail" folders. Long talks with GFI producing no results.

My Results:
I've narrowed it down to the Bayesian filter that's doing the dirty(GFI Log Entry):-
"08/14/08 16:23:07","MailWare","jan.adam@rvluk.co.uk","carol.pesta@rvluk.co.uk","RE:  [Scanned]","Moved to Exchange Junk folder","Bayesian Filter detected spam"

More Info:
Switching the Bayesian filter off fixes it, so does adding the domains to the whitelist(but GFI really don't like you doing the whitelist thing!). As the Bayesian filter is the most effective I may as well uninstall GFI unless anyone here can throw more light ion the problem?
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