Setting a Master to be based on another Master (AppleScript)

I have a bunch of documents usually with around 30 master pages that need to be based on a pagination master. I get a polite message that this does not work (though it compiles). How can I exclude the AA-Pagination master from the list and how can I get AppleScript to have all the other master spreads (except blank or none) to be based on the spread called AA-Pagination

tell application "Adobe InDesign CS3"
set myDoc to active document
tell myDoc
set applied master of every master spread to "AA-Pagination"
end tell
end tell

Thanks for any help