This may be related to the state validation added in 1562 which seems to break stacked states for Insteon devices. 
Happy to provide more info if needed but it should be pretty easy to replicate.

From: Dan Uribe []
Sent: Friday, December 26, 2008 11:19 AM
To: ''
Subject: [mh] Insteon set_with_timer

Functionality seems to break in SVN Revision 1573.  Object gets set to desired initial state but the timer hash/slice is never set (or is nearly instantly removed) so subsequent event(s) never fire.
Thanks in advance.