redirect doesn't work in eval

[Marc Lambrichs]

When a request is sent to the webserver, it handles some stuff and then 
- sometimes - a redirect must take place. Now the weird part:

when i use
$r->headers_out->set( Location => 'http://www.mysite.com/' );
return Apache2::Const::REDIRECT
inside an eval{} construction it doesn't work. Is there any logic to this?
Marc