FS-6250 fix regression from 7efeabbd, don't…

FS-6250 fix regression from 7efeabbd, don't discrimiate against people that have s as the first character in their user names

src/switch_utils.c

@@ -3123,7 +3123,7 @@ SWITCH_DECLARE(int) switch_split_user_domain(char *in, char **user, char **domai
 
 	if (!strncasecmp(in, "sip", 3)) {
 		in += 3;
-		while(*in == ':' || *in == 's') in++;
+		while(*in == ':') in++;
 	}
 
 	u = in;