Applescript to change account settings

I am trying to write and applescript to change the exchange account settings for partially retrieving messages. this is what i have so far, but it dose not seem to be working.

tell application "Microsoft Entourage"
	set partially retrieve messages to true
	set partially retrieve messages size to 9999
end tell

From the dictionary, it looks like partially retrieve messages is a property of an Exchange account, not of the application. Try adding a “tell exchange account AccountName” after the “Tell Application” line

This is what worked for me.

tell application "Microsoft Entourage"
	tell default mail account
		set partially retrieve messages to true
		set partially retrieve messages size to 9999
	end tell
end tell