Index: lib/Mail/SpamAssassin/BayesStore/DBM.pm
===================================================================
--- lib/Mail/SpamAssassin/BayesStore/DBM.pm	(revision 606514)
+++ lib/Mail/SpamAssassin/BayesStore/DBM.pm	(working copy)
@@ -279,7 +279,11 @@
     my $name = $path.'_'.$dbname;
     my $db_var = 'db_'.$dbname;
     dbg("bayes: tie-ing to DB file R/W $name");
-    tie %{$self->{$db_var}},$self->DBM_MODULE,$name, O_RDWR|O_CREAT,
+
+    ($self->DBM_MODULE eq 'DB_File') and
+         Mail::SpamAssassin::Util::avoid_db_file_locking_bug ($name);
+
+    tie %{$self->{$db_var}},$self->DBM_MODULE, $name, O_RDWR|O_CREAT,
 		 (oct($main->{conf}->{bayes_file_mode}) & 0666)
        or goto failed_to_tie;
   }
Index: lib/Mail/SpamAssassin/DBBasedAddrList.pm
===================================================================
--- lib/Mail/SpamAssassin/DBBasedAddrList.pm	(revision 606514)
+++ lib/Mail/SpamAssassin/DBBasedAddrList.pm	(working copy)
@@ -82,15 +82,19 @@
 
     dbg("auto-whitelist: tie-ing to DB file of type $dbm_module $mod1 in $path");
 
+    ($self->{is_locked} && $dbm_module eq 'DB_File') and 
+            Mail::SpamAssassin::Util::avoid_db_file_locking_bug ($path);
+
     if (! tie %{ $self->{accum} }, $dbm_module, $path, $mod2,
-      oct($main->{conf}->{auto_whitelist_file_mode}) ) {
-        my $err = $!;   # might get overwritten later
-        if ($self->{is_locked}) {
-          $self->{main}->{locker}->safe_unlock($self->{locked_file});
-          $self->{is_locked} = 0;
-        }
-        die "auto-whitelist: cannot open auto_whitelist_path $path: $err\n";
+            oct($main->{conf}->{auto_whitelist_file_mode}) )
+    {
+      my $err = $!;   # might get overwritten later
+      if ($self->{is_locked}) {
+        $self->{main}->{locker}->safe_unlock($self->{locked_file});
+        $self->{is_locked} = 0;
       }
+      die "auto-whitelist: cannot open auto_whitelist_path $path: $err\n";
+    }
   }
 
   bless ($self, $class);
Index: lib/Mail/SpamAssassin/Util.pm
===================================================================
--- lib/Mail/SpamAssassin/Util.pm	(revision 606514)
+++ lib/Mail/SpamAssassin/Util.pm	(working copy)
@@ -57,6 +57,7 @@
 
 use Config;
 use File::Spec;
+use File::Basename;
 use Time::Local;
 use Sys::Hostname (); # don't import hostname() into this namespace!
 use Fcntl;
@@ -1551,6 +1552,32 @@
 
 ###########################################################################
 
+# bug 5612: work around for bugs in Berkeley db 4.2
+#
+# on 4.2 having the __db.[DBNAME] file will cause an loop that will never finish
+# on 4.3+ the loop will timeout after 301 open attempts, but we will still
+# be unable to open the database.  This workaround solves both problems. 
+#
+sub avoid_db_file_locking_bug {
+  my ($path) = @_;
+
+  my $db_tmpfile = untaint_file_path(File::Spec->catfile(dirname($path),
+                        '__db.'.basename($path)));
+
+  # delete "__db.[DBNAME]" and "__db.[DBNAME].*"
+  foreach my $tfile ($db_tmpfile, <$db_tmpfile.*>) {
+    my $file = untaint_file_path($tfile);
+    next unless (-e $file);
+
+    dbg("Berkeley DB bug work-around: cleaning tmp file $file");
+    if (!unlink($file)) {
+      die "cannot remove Berkeley DB tmp file $file: $!\n";
+    }
+  }
+}
+
+###########################################################################
+
 1;
 
 =back