Handling XML through input->post

[eluser]msteudel[/eluser]
So I'm receiving some xml via http POST like so:

$xml = $this->input->post('request');

Obviously CI protects against XSS, but in this case I actually want the various entities intact, e.g. converting < to &lt;

So is there a proper way to indicate this? I tried doing

$xml = $this->input->post( 'request', false );

But that didn't work.

I can of course do something like:

$xml = html_entities_decode( $this->input->post( 'request' ) );

TIA, Mark