Find out the existance of an element between 2 others

Hi,

I'm working with some WordML at present, trying to identify if a page is
blank so that I can remove it.

Unfortunately, there is no <page> tag, otherwise things would be a lot
easier.
Instead, pages are delimited using the <w:br> tag.  Valid text elements
are wrapped in <w:t> tags.

What I am trying to express in an Xpath is
"Look to see where there are any <w:t> elements containing text between
these 2 <w:br>s".  I can understand how to see whether there are any
<w:t> after a <w:br> using axes. What I don't get is how to tell it that
all the <w:t> below the next <w:br> should be excluded.  Any thoughts?

Cheers,
    Ed

P.s. how do I reply back to this thread afterwards?