diff --git a/Lib/sre.py b/Lib/sre.py
index e6550977fff..7b79f43d8d6 100644
--- a/Lib/sre.py
+++ b/Lib/sre.py
@@ -170,6 +170,7 @@ def _subn(pattern, template, text, count=0, sub=0):
     else:
         template = _compile_repl(template, pattern)
         literals = template[1]
+        sub = 0 # temporarly disabled, see bug #449000
         if (sub and not count and pattern._isliteral() and
             len(literals) == 1 and literals[0]):
             # shortcut: both pattern and string are literals