That code works for me, but it's pretty ugly.

This works nearly universally but is only good for one line:

$|=1;  # switch off buffering or this won't work
print "please wait";
do_something();
print "\rthanks for waiting\n";
[download]

Note the \r return character. You can also use the \b backspace char.

If you can rely on having an ANSI terminal you can do a lot of interesting tricks. see a quick list. Or search CPAN for ANSI and Term.