diff --git a/lib/Travel/Status/DE/HAFAS.pm b/lib/Travel/Status/DE/HAFAS.pm
index 9800ddff0870f5a9b52420db1a8da3a0797dbb00..bf69bc586a7e6549bf7c254c6f6f3b6f1706ae57 100644
--- a/lib/Travel/Status/DE/HAFAS.pm
+++ b/lib/Travel/Status/DE/HAFAS.pm
@@ -160,6 +160,10 @@ sub new {
 		  =~ s{ lead = " \K ( [^"]+ ) }{ $1 =~ s{ < [^>]+ > }{}grx }egx;
 	}
 
+	# TODO the DB backend also retuns invalid XML (similar to above, but with
+	# errors in delay="...") when setting the language to dutch/italian.
+	# No, I don't know why.
+
 	if ( $ref->{developer_mode} ) {
 		say $ref->{raw_xml};
 	}