Index: trunk/lib/MP3/Find/Base.pm
===================================================================
--- trunk/lib/MP3/Find/Base.pm	(revision 6)
+++ trunk/lib/MP3/Find/Base.pm	(revision 7)
@@ -42,8 +42,11 @@
     
     foreach (keys %QUERY) {
-        # so we don't have spurious warnings when trying to match against undef
-        delete $QUERY{$_} unless defined $QUERY{$_};
-        # package everything uniformly, so subclasses don't need to unpack it
-        $QUERY{$_} = [ $QUERY{$_} ] unless ref $QUERY{$_} eq 'ARRAY';
+        if (defined $QUERY{$_}) {
+            # package everything uniformly, so subclasses don't need to unpack it
+            $QUERY{$_} = [ $QUERY{$_} ] unless ref $QUERY{$_} eq 'ARRAY';
+        } else {
+            # so we don't have spurious warnings when trying to match against undef        
+            delete $QUERY{$_};
+        }
     }