HTML comments are (normally) ignored by the browser: they are not used to build the DOM tree. Thus they are not a good place to put information that should be sent back to the server.
I can't understand what you are trying to accomplish but you should probably be using hiddend fields:
<input type="hidden" name="foo" value="bar">
Álvaro G. Vicario
2010-07-06 12:06:40