diff --git a/phsource/ph_vietnam b/phsource/ph_vietnam
index 6c8a6308..d42ea4b1 100644
--- a/phsource/ph_vietnam
+++ b/phsource/ph_vietnam
@@ -274,7 +274,7 @@ phoneme o
 	length 180
   ENDIF
   //FMT(vowel/o)  // o_2)
-  FMT(vietnam/o)
+  FMT(vietnam/o_2)
 endphoneme
 
 
diff --git a/phsource/vietnam/O b/phsource/vietnam/o_2
similarity index 100%
rename from phsource/vietnam/O
rename to phsource/vietnam/o_2