diff --git a/src/regexp.c b/src/regexp.c
index f8b8616..e212cc0 100644
--- a/src/regexp.c
+++ b/src/regexp.c
@@ -742,7 +742,7 @@
 {
 #ifdef FEAT_MBYTE
     if (enc_utf8 || STRCMP(p_enc, "latin1") == 0
-					      || STRCMP(p_enc, "latin9") == 0)
+					 || STRCMP(p_enc, "iso-8859-15") == 0)
 #endif
     {
 	switch (c)