Header/Footer printing margins

I have a form with an header containing &W followed by two tabs and page number.Page number is right adjusted but I cannot define the width of the header itself.

The result is a 16cm wide header above a 17cm wide document body, not very nice.

How can I set the header to be 17cm wide ?

Thanks

Subject: Header/Footer printing margins

cannot be set

http://www-1.ibm.com/support/docview.wss?rs=899&uid=swg21102296