Bug 311489 Bug entry makes user choose classification even if only one is enterable

enter_bug.cgi

@@ -76,11 +76,25 @@ if (!defined $product || $product eq "") {
 
     if ( ! Param('useclassification') ) {
         # just pick the default one
-      $cgi->param(-name => 'classification', -value => (keys %::classdesc)[0]);
+        $cgi->param(-name => 'classification', 
+                    -value => (keys %::classdesc)[0]);
     }
 
     if (!$cgi->param('classification')) {
         my $classifications = Bugzilla->user->get_selectable_classifications();
+        foreach my $classification (@$classifications) {
+            my $found = 0;
+            foreach my $p (@enterable_products) {
+               if (CanEnterProduct($p)
+                   && IsInClassification($classification->{name},$p)) {
+                       $found = 1; 
+               }
+            }
+            if ($found == 0) {
+                @$classifications = grep($_->{name} ne $classification->{name},
+                                         @$classifications);
+            }
+        }
 
         if (scalar(@$classifications) == 0) {
             ThrowUserError("no_products");