diff --git a/main/pbx.c b/main/pbx.c
index 343ed85dfd785119d5e8a9ff014631ff7158ed2f..8f6fb83ffb641cb01afd8955ab9f908280901168 100644
--- a/main/pbx.c
+++ b/main/pbx.c
@@ -1483,7 +1483,7 @@ static int ext_cmp1(const char **p)
 		;	/* ignore some characters */
 
 	/* always return unless we have a set of chars */
-	switch (c) {
+	switch (toupper(c)) {
 	default:	/* ordinary character */
 		return 0x0000 | (c & 0xff);