Counting Characters of selection in Quark6

I need help to make a script that counts the characters of a textselection in Quark Xpress Passport 6.0 in Panther and display the result in a dialog box.

This works for Quark 6 / OS 10.3.2.

tell application "QuarkXPress Passport"
	tell document 1
		set theSel to selection
		if class of theSel is text then
			set characterCount to count of characters of theSel
			display dialog ("Number of characters in this selection is " & characterCount)
		else
			display dialog ("Select some text ")
		end if
	end tell
end tell

Thanks very much!
Exactly what I wanted.