[Evolution] spam filter or not to spam filter

[michael <cs networkingnewsletter org uk>]

When I first start evolution and it fetches new mail from 6 accounts, it
seems that often not all new emails are checked for spam. For example,
if I later select a bunch of new emails and manually "check for junk"
then indeed many of the new emails are flagged as spam.

I'm running Evolution 2.6.3 under Debian (seems to happen for both
'etch' and 'unstable')

I've had a quick look in /var/log/syslog but nothing jumps out as to why
this may be happening.

All suggestions welcome.
Thanks, Michael