mail rule script won't create an outgoing message

I’m trying to make a mail rule which is sending a new e-mail message based on certain criteria. It wasn’t working and after a lot of troubleshooting I sort of nailed down the problem. It refuses to create a new outgoing message.
I stripped the rule of everything except this one command and it still doesn’t work. here is the script:


using terms from application "Mail"
	on perform mail action with messages theSelectedMessages for rule theRule
		repeat with msg in theSelectedMessages
			-- Process the current message
			
			
			
			tell application "Mail"
				
				make new outgoing message with properties {visible:true, subject:"let's try this", content:"blah"}
				
			end tell
			
			
		end repeat
	end perform mail action with messages
end using terms from

When I try to apply it to messages in Mail nothing happens and the console spews out the following:
27/02/08 2:38:35 PM Mail[394] *** Assertion failure in -[MailDocumentEditor load], /SourceCache/Mail/Mail-919/Compose.subproj/DocumentEditor.m:322

What in the world is going on here? Am I doing something wrong?

Hi,

Do you use Leopard?

It seems to be a real bug.

yes, I use 10.5.2

If it’s a bug, is it a known bug? have you heard of it? should I report it?
Thanks.

I read something about it in the Apple Discussions,
and I’ve tested it also without success on my machine