I know this is an old question, but it is worth mentioning what we have tried. We used a slight work around for this. All our template content makes use dynamically rendered xhtml maintained in a CKEditor. To force the page breaks in Word we used a line with the following:
<div style="page-break-before: always;">
I just ran our testproject for this in version 188.8.131.52, seems to work fine. Can you please submit an incident with a sample project?