+PH/04 The variables $auth1, $auth2, $auth3 are now available in authenticators,
+ containing the same values as $1, $2, $3. The new variables are provided
+ because the numerical variables can be reset during string expansions
+ (for example, during a "match" operation) and so may lose the
+ authentication data. The preferred variables are now the new ones, with
+ the use of the numerical ones being deprecated, though the support will
+ not be removed, at least, not for a long time.
+