SpamAssassin filter

I’m running RT 3.0.6 and attempted to enable the Filter::SpamAssassin
module as per rt-mailgate’s POD, which resulted in:

No GetCurrentUser code found in \
RT::Interface::Email::Filter::SpamAssassin module \
at /usr/local/rt3/lib/RT/Interface/Email.pm line 524.

I see this referred to in:
http://lists.fsck.com/pipermail/rt-devel/2003-March/003637.html
http://lists.fsck.com/pipermail/rt-devel/2003-June/004206.html
… but without resolution. Is this a known issue?

Regards,
Tom Howell-Cintron