+/*************************************************
+* Elaborate message for bad variable *
+*************************************************/
+
+/* For the "unknown variable" message, take a look at the variable's name, and
+give additional information about possible ACL variables. The extra information
+is added on to expand_string_message.
+
+Argument: the name of the variable
+Returns: nothing
+*/
+
+static void
+check_variable_error_message(uschar *name)
+{
+if (Ustrncmp(name, "acl_", 4) == 0)
+ expand_string_message = string_sprintf("%s (%s)", expand_string_message,
+ (name[4] == 'c' || name[4] == 'm')?
+ (isalpha(name[5])?
+ US"6th character of a user-defined ACL variable must be a digit or underscore" :
+ US"strict_acl_vars is set" /* Syntax is OK, it has to be this */
+ ) :
+ US"user-defined ACL variables must start acl_c or acl_m");
+}
+
+
+