Steps to Reproduce

$ cat - > test.html
<style>                                                                                   
    @page foo { background: #FFFE98; }
    h1 { page: foo; }
</style>

<h1>Testing</h1>
<p>I love cheese.</p>
$ prince-7.1-macosx/lib/prince/bin/prince test.html 
$ open -a Preview test.pdf 
$

Expected

One page, highlighted background yellow.


Actual

Two pages, first highlighted background yellow with H1 on it, second with P on it.


P.S.

Seriously? I can't attach PDFs?

This is the expected behaviour for named pages at this time. You can use an unnamed page, or put the paragraph following the heading in the named page as well, or apply the named page to a wrapper div element. (I've tweaked the forum admin settings, not sure why it was preventing PDF attachments).