DOCBOOK-APPS: Different margins for recto and verso pages forbinding/spine

Hi,

Has anyone been able to use different margins for recto and verso pages so
that you can account for the binding of a document?

Regards
-------
Richard Sharpe, 
Samba (Team member, www.samba.org), Ethereal (Team member, www.ethereal.com)
Contributing author, SAMS Teach Yourself Samba in 24 Hours
Author, Special Edition, Using Samba