Changing page orientation within a document

Hi,

I would like just some pages to be in landscape (those with sample reports 
on them), the rest in portrait in a PDF, using XSL stylesheets.

By editing the intermediate FO file and modifying a page-master I can 
certainly get XEP to mix page orientations.

So the steps are:

1)	Add more page-masters for the other orientation (easy)

2)	Define PIs so that following pages use the 'other' page-masters (eg. 
<?landscape?> and <?portrait?>).

Any pointers and help with step 2 would be appreciated.


Thanks.


David Brooks