[CentOS] Evolution Woes

Somewhat OT as this may not be CentOS/EL-specific.  I am seeking help in
trying to determine why the combination of my work e-mail server and
evolution is usually, but not always, giving the error

        Error verifying signature
        Cannot verify message signature: Incorrect message format
        
on signed messages (such as those from Ralph Angenendt and Johnny
Hughes), and refusing to display them; while the same messages are
readable with a webmail interface, in the list archives, or when they go
to my home address that is also subscribed to some of the same lists
(same version of evolution at home and work).  This problem only started
last week and the origin is probably related to infrastructure upgrades
on the mail server, over which I have no control.

Google has not come through on this one .  Many of the results seem to
lead to sources or change-logs containing the strings, not to similar
problem reports of fixes.  Can't find anything relevant in
bugzilla.gnome.org, bugzilla.ximian.com, bugzilla.redhat.com, or
bugs.centos.org.  Have searched without success in the evolution docs
and on-line for a way to turn off the checks in evolution so the message
will display.

Has anyone else seen this behavior?

Anyone have a fix or work-around?

Thanks,
Phil