Escaping scriptlets <% and %> in view templates

JSP spec indicates that scriptlet tags <% and %> can be escaped as <\% and %\> respectively. I have tried every combination of \<%, \<% and %>, %\>, \%\> etc that I can think of and all of them appear to produce complaints about unexpected "\" when I generate views:

hello
<\%
	def h = "Mad World";
%\>
world

produces:

org.codehaus.groovy.control.MultipleCompilationErrorsException: startup failed,
Script1.groovy: 3: unexpected char: '\' @ line 3, column 13.
1 error
...

whereas

hello
<% 
	def h = "Mad World";
%>
world

produces no errors but generates the following view (as expected):

hello

world