diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index b2bcae791..4f3b30876 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,7 @@
+2008-12-02  Corinna Vinschen  <corinna@vinschen.de>
+
+	* fhandler_registry.cc (must_encode): Fix condition changed for testing.
+
 2008-12-01  Christian Franke  <franke@computer.org>
 
 	* fhandler_registry.cc (must_encode): New function.
diff --git a/winsup/cygwin/fhandler_registry.cc b/winsup/cygwin/fhandler_registry.cc
index f77e85c4d..ce4335fd9 100644
--- a/winsup/cygwin/fhandler_registry.cc
+++ b/winsup/cygwin/fhandler_registry.cc
@@ -85,7 +85,7 @@ static HKEY open_key (const char *name, REGSAM access, DWORD wow64, bool isValue
 static inline bool
 must_encode (char c)
 {
-  return (isdirsep (c) || c == '%');
+  return (isdirsep (c) || c == ':' || c == '%');
 }
 
 /* Encode special chars in registry key or value name.