Single Comment Escape, does it work?

[gcl]

Does the singlecommentesc keyword works?
The language uses ! as a comment and it also uses ! to escape it.
So the following code

case msg^dest.route^ty of
begin
! 0! case msg^dest.route^st of
begin

should be

case msg^dest.route^ty of
begin
! 0! case msg^dest.route^st of
begin

The syntax file looks like this ( The TAL.SYN)
[Syntax]
Namespace1 = 6
IgnoreCase = Yes
InitKeyWordChars = A-Za-z_^
KeyWordChars = A-Za-z0-9_^
BracketChars=[]()
OperatorChars = -+*/<>!~%&|=@
PreprocStart = ?
SyntaxStart =
SyntaxEnd =
CommentStart =
CommentEnd =
CommentStartAlt =
CommentEndAlt =
SingleCommentEsc = !
SingleComment = !
SingleCommentCol =
SingleCommentAlt = --
SingleCommentColAlt =