[horde] Security Enhancement Request

[Brent]

Would like the ability to prevent devices from connecting via  
ActiveSync.  After a user has established their device(s), a checkbox  
in the Preferences->ActiveSync that says something like "Allow  
ActiveSync Devices" which would toggle between allow/disallow  
connections from new devices.  In this way, you prevent other devices  
from being able to access (via ActiveSync anyhow) the mailbox.  If it  
were set to disallow, the error message should be the same as a "bad  
password" message.

If you had the CEO with email, you wouldn't want people to keep firing  
a user/pass combo at your ActiveSync installation.