[docbook-apps] incorrect number of pages

Hi

I use the mechanism described in the following article

http://www.sagehill.net/docbookxsl/PrintHeaders.html#PageXofY

to print the total number of pages.

It works pretty well, but from time to time I get an empty page at the end of the book and the total number of pages includes that empty page. It happens when the content of the book fills all the pages and the only thing left (i.e. output at the last page is the <fo:block id="END-OF-DOCUMENT"/> element. 

Is there a way to avoid such issue.

Thanks,

Robert