diff --git a/ftdetect/ttcn.vim b/ftdetect/ttcn.vim
index 69dae6e..9d10eb8 100644
--- a/ftdetect/ttcn.vim
+++ b/ftdetect/ttcn.vim
@@ -1,2 +1,2 @@
 " TTCN filetype
-au BufRead,BufNewFile *.ttcn set filetype=ttcn
+au BufRead,BufNewFile *.{ttcn,ttcn3} set filetype=ttcn