diff --git a/src/include/switch_utils.h b/src/include/switch_utils.h
index 1b965b4a76..466bc22541 100644
--- a/src/include/switch_utils.h
+++ b/src/include/switch_utils.h
@@ -514,7 +514,7 @@ SWITCH_DECLARE(char *) switch_separate_paren_args(char *str);
 SWITCH_DECLARE(const char *) switch_stristr(const char *instr, const char *str);
 SWITCH_DECLARE(switch_bool_t) switch_is_lan_addr(const char *ip);
 SWITCH_DECLARE(char *) switch_replace_char(char *str, char from, char to, switch_bool_t dup);
-SWITCH_DECLARE(switch_bool_t) switch_ast2regex(char *pat, char *rbuf, size_t len);
+SWITCH_DECLARE(switch_bool_t) switch_ast2regex(const char *pat, char *rbuf, size_t len);
 
 /*!
   \brief Escape a string by prefixing a list of characters with an escape character
diff --git a/src/switch_regex.c b/src/switch_regex.c
index 697ba1cf62..aee8f2b9e3 100644
--- a/src/switch_regex.c
+++ b/src/switch_regex.c
@@ -60,11 +60,18 @@ SWITCH_DECLARE(int) switch_regex_perform(const char *field, const char *expressi
 	int match_count = 0;
 	char *tmp = NULL;
 	uint32_t flags = 0;
+	char abuf[256] = "";
 
 	if (!(field && expression)) {
 		return 0;
 	}
 
+	if (*expression == '_') {
+		if (switch_ast2regex(expression + 1, abuf, sizeof(abuf))) {
+			expression = abuf;
+		}
+	}
+	
 	if (*expression == '/') {
 		char *opts = NULL;
 		tmp = strdup(expression + 1);
diff --git a/src/switch_utils.c b/src/switch_utils.c
index 8b3088f03f..5829140098 100644
--- a/src/switch_utils.c
+++ b/src/switch_utils.c
@@ -565,9 +565,9 @@ SWITCH_DECLARE(switch_bool_t) switch_is_lan_addr(const char *ip)
 		)? SWITCH_FALSE : SWITCH_TRUE;
 }
 
-SWITCH_DECLARE(switch_bool_t) switch_ast2regex(char *pat, char *rbuf, size_t len)
+SWITCH_DECLARE(switch_bool_t) switch_ast2regex(const char *pat, char *rbuf, size_t len)
 {
-	char *p = pat;
+	const char *p = pat;
 
 	if (!pat) {
 		return SWITCH_FALSE;