Slow cperl-mode in emacs 22 & 23

[Hinrik Örn Sigurðsson]

I'm new to emacs and the first thing I tried after installing it was
to edit a Perl file (~3000 lines) and switch to cperl-mode (via M-x
cperl-mode). Moving around in the file with cperl-mode is very slow. I
have to wait at least a second to see results after hitting Page Down.
Editing smaller files (~500 lines) is faster but still a little
sluggish. The default perl-mode is very fast in all cases.

I have done no configuration (no ~/.emacs or ~/.emacs.d). I tried
emacs 22.2 and two snapshots of emacs 23 (2008-10-13 and 2009-03-20),
they all have this speed issue in cperl-mode. I'm running Ubuntu 8.10.