Reset Connection on Submit, if any PHP is added to the output

Issue Summary

This is the first time this has happened to me with Contemplate, and I've used it one another site, before. I'm trying to affect the RSS output, and it will NOT save at all if there is ANY php in the code.

This is the "offending" code I'm trying to use:
<?php print $node->field_featured_teaser[0]['view'] ?>

I click submit, and it says:

Page Load Error: Connection Interrupted. The connection to the server was reset while the page was loading. The network link was interrupted while negotiating a connection. Please try again.

Now, if I put in regular text or html, it works just fine. :|
Any ideas?