[Mimedefang] multiplexor and BayesStore.pm error

[Mary Verge DeSisto]

I am seeing this error in my mail log:
Feb 11 06:12:24 connery mimedefang-multiplexor: [ID 980602 mail.info] Slave 27 
stderr: Use of uninitialized value in numeric eq (==) at 
/u01/perl-5.6.1/lib/site_perl/5.6.1/Mail/SpamAssassin/BayesStore.pm line 1440.

Feb 11 06:12:24 connery mimedefang-multiplexor: [ID 980602 mail.info] Slave 27 
stderr: Use of uninitialized value in numeric eq (==) at 
/u01/perl-5.6.1/lib/site_perl/5.6.1/Mail/SpamAssassin/BayesStore.pm line 1426.

This is what is at line 1440 and 1426 in BayesStore.pm:
if ( $self->{db_version} == 0 ) {

also:
  my $self = {
    'bayes'             => $bayes,
    'already_tied'      => 0,
    'is_locked'         => 0,
    'string_to_journal' => '',
    'db_version'        => undef,
  };
  
I am a perl newbie, but it looks like it may have something to do with, 
"'db_version'        => undef,".

I can run sa-learn --rebuild with no problem.  Any ideas/troubleshooting tips?

MIMEDefang 2.37
SpamAssassin 2.61
DB_File 1.806

thanks,
-Mary