Logout button conflicts with wp-slimstat

I’m using the Theme My Login plugin which comes with a logout button. The link points to [site url]/logout/?_wpnonce=xxxxxxxxxx.

This seems to be conflicting with something in wp-slimstat. I get a page full of errors. There are two different errors, the first one is:

Notice: Undefined variable: slimstat_patterns in [site path]/wp-content/plugins/wp-slimstat/wp-slimstat.php on line 663

This one only appears once. The other one appears multiple times, but with a different pluggable.php line number.

Warning: Cannot modify header information – headers already sent by (output started at [site path]/wp-content/plugins/wp-slimstat/wp-slimstat.php:663) in [site path]/wp-includes/pluggable.php on line 698

The function being referred to in wp-slimstat is _get_browser(), and line 663 is:

if (!is_array($slimstat_patterns)) return $browser;

Is this something I can fix with a setting or something?

Thanks,

Angus

http://wordpress.org/plugins/wp-slimstat/