Move mail message no longer works with snow leopard (10.6)

I used to have a script which goes through my Inbox every night, filing messages away depending on email address into sub folders.

Everything was fine until I upgraded to 10.6 and then it stopped working!! ;((((

on mess_han(person, place_to)
tell application “Mail”
tell inbox
set theMessage to messages whose sender contains person
end tell

		move theMessage to mailbox (place_to) of account (".Mac")
	end tell
end try

end mess_han

–error “Mail got an error: Can’t get mailbox "Info/Offers" of inbox.” number -1728 from mailbox “Info/Offers” of inbox

Has anybody got any ideas on how to fix this problem?