Error -609

I have a script that gets some of Mail's Mailbox Behaviors and if not set correctly it ...
1. Quits Mail;
2. Writes the correct behaviors to com.apple.mail.plist;
3. Activates Mail.

In Snow Leopard, it works perfectly.
In Leopard (10.5.8), I get Error = -609, Mail got an error. Connection is invalid.
Consistently, every time.

Fixed the problem!

My original script did something like this ...

tell application "Mail"

try

set frontViewer to (some message viewer whose index is 1)

on error

error "A message viewer window must be open and frontmost in Mail."

end try

my setMailboxBehavior(frontViewer) -- verify and set common mailbox behaviors

set mailBoxList to (selected mailboxes of frontViewer) as list

It didn't cause a problem in Snow Leopard, but in Leopard, whenever setMailboxBehavior quit, then activated Mail, the value of frontViewer was no longer valid and caused the -609 error.

So, I changed the script to ...

my setMailboxBehavior() -- verify and set common mailbox behaviors

tell application "Mail"

try

set frontViewer to (some message viewer whose index is 1)

on error

error ("A message viewer window must be open and frontmost in Mail.")

end try

set mailBoxList to (selected mailboxes of frontViewer) as list

where the handler, setMailboxBehavior, now gets the value of frontViewer internally.

I just tested this in 10.5.8 and the -609 error no longer appears.