the_content does not Output Correctly

Hi,

I am trying to create a new page template. For some reasons, the_content() call does not output anything when it is not preceded with get_header(). When there is get_header() before the_content(), the_content() outputs correctly.

In my code, I need to use a different page header so I am using:
include(TEMPLATEPATH . '/new_header.php');

Is there something I need to include in order to make the_content() pulls the content?

Thank you.