diff -r f593b7acdb37 -r b59a964f37ef uh_parser/uh.pl
--- a/uh_parser/uh.pl	Thu May 06 18:06:35 2010 +0100
+++ b/uh_parser/uh.pl	Mon May 10 12:03:05 2010 +0100
@@ -504,7 +504,7 @@
 	if (defined $allpackages->{'unknown/unknown'})
 	{
 		push @sorted, 'unknown/unknown';
-		undef $allpackages->{'unknown/unknown'};
+		delete $allpackages->{'unknown/unknown'};
 	}
 	push @sorted, sort {$a cmp $b} keys %{$allpackages};