-=item Warning: undeclared Alias referenced near ...
-
-Either you are using a {User,Runas,Host,Cmnd}_Alias before
-defining it or you have a user or hostname listed that
-consists solely of uppercase letters, digits, and the
-underscore ('_') character. If the latter, you can ignore
-the warnings (B<sudo> will not complain). In B<-s> (strict)
-mode these are errors, not warnings.
-
-=item Warning: runas_default set after old value is in use ...
-
-You have a I<runas_default> Defaults setting listed in the I<sudoers>
-file after its value has already been used. This means that entries
-prior to the I<runas_default> setting will match based on the default
-value of I<runas_default> (C<@runas_default@>) whereas entries
-B<after> the I<runas_default> setting will match based on the new
-value. This is usually unintentional and in most cases the
-<runas_default> setting should be placed before any C<Runas_Alias>
-or User specifications. In B<-s> (strict) mode this is an error,
-not a warning.
+=item Warning: {User,Runas,Host,Cmnd}_Alias referenced but not defined
+
+Either you are trying to use an undeclare {User,Runas,Host,Cmnd}_Alias
+or you have a user or hostname listed that consists solely of
+uppercase letters, digits, and the underscore ('_') character. In
+the latter case, you can ignore the warnings (B<sudo> will not
+complain). In B<-s> (strict) mode these are errors, not warnings.
+
+=item Warning: unused {User,Runas,Host,Cmnd}_Alias
+
+The specified {User,Runas,Host,Cmnd}_Alias was defined but never
+used. You may wish to comment out or remove the unused alias. In
+B<-s> (strict) mode this is an error, not a warning.