--- a/mercurial/hgweb/webcommands.py	Tue Jan 22 09:28:51 2008 +0100
+++ b/mercurial/hgweb/webcommands.py	Tue Jan 22 12:31:55 2008 +0100
@@ -30,7 +30,7 @@
     path = fctx.path()
     text = fctx.data()
     mt = mimetypes.guess_type(path)[0]
-    if util.binary(text):
+    if mt is None or util.binary(text):
         mt = mt or 'application/octet-stream'
 
     req.httphdr(mt, path, len(text))