Did you change the username?
Anyway, I thought I'd share a php script I wrote a while back to show Linode stats, you can find it here:
http://www.zer0day.com/bw.phps
Edit the username, at the end of the 3rd 'define', add a username and password sha256 hash where it says, and it should work fine.
You can find the live version here:
http://www.zer0day.com/bw.php
I made a few small changes from my old one to show the uptime in days using php, since I don't feel comfortable leaving the shell() et al functions enabled in php.