ob_start() error: caused by Gzip compression?

[eluser]codex[/eluser]
A friend is getting this error

Code:

'Fatal error: ob_start() [<a href=’ref.outcontrol’>ref.outcontrol</a>]: Cannot use output buffering in output buffering display handlers in ~PATH_TO_CODEIGNITER_ROOT~\libraries\Exceptions.php on line 160'

on this page: http://www.graffr.com/explore/

At home (Firefox 2.0.0.8) I'm getting the same, but at the office no error. I've tested it on FF 2.0.0.8, IE7 and IE6, but no error.

Could it be caused by Gzip compression enabled in config.php?