p4raw-id: //depot/perl@18819
=item PERL_UNICODE
-Equivalent to the B<-C> command-line switch.
+Equivalent to the B<-C> command-line switch. Note that this is not
+a boolean variable-- setting this to C<"1"> is not the right way to
+"enable Unicode" (whatever that would mean).
=item SYS$LOGIN (specific to the VMS port)