sitemesh excludes having no effect - sitemesh

Question

I am replacing a GUI based on RForms with one based on GWT and I want to keep the RForms one available for fiddling with test data until the GWT UI is ready to take over. (This is probably not important to my question, I just wanted to give an idea of WHY I'm doing what might appear to be a bit of a silly thing).
I'm using Sitemesh to wrap my GWT GUI in a header and footer which is common to the rest of the system. Unfortunately if Sitemesh gets its paws on the RForms GUI, the styling breaks the functionallity of the page and the RForms GUI becomes unusable.
I have tried to solve this by setting up SiteMesh to exclude the URLs on which the RForms GUI is served, but it doesn't seem to be working, no matter what I do I either get all pages decorated or none. My Sitemesh setup is as follows:
Sitemesh.xml
<sitemesh>
<property name="decorators-file" value="/WEB-INF/decorators.xml"/>
<excludes file="${decorators-file}"/>
<property name="excludes-file" value="/WEB-INF/sitemesh-excludes.xml"/>
<excludes file="${excludes-file}"/>
<page-parsers>
<parser content-type="text/html"
class="com.opensymphony.module.sitemesh.parser.HTMLPageParser"/>
<parser content-type="text/html;charset=ISO-8859-1"
class="com.opensymphony.module.sitemesh.parser.HTMLPageParser"/>
</page-parsers>
<decorator-mappers>
<mapper class="com.opensymphony.module.sitemesh.mapper.ConfigDecoratorMapper">
<param name="config" value="${decorators-file}"/>
</mapper>
</decorator-mappers>
</sitemesh>
decorators.xml
<decorators defaultdir="/decorators">
<decorator name="main" page="main.jsp">
<pattern>/*</pattern>
</decorator>
</decorators>
sitemesh-excludes.xml
<decorators>
<excludes>
<pattern>/*/hostedmode.*</pattern>
<pattern>/*/download.*</pattern>
<pattern>/list/*</pattern>
<pattern>/entity/*</pattern>
<pattern>/rest/*</pattern>
<pattern>/dwr/*</pattern>
</excludes>
</decorators>
This setup results in all pages being decorated regardless of the excludes file. I have also tried putting the excludes in the same file as the decorators, with the same result. I'm sure I'm doing something stupid, but I can't see it, can anyone explain to me how to prevent sitemesh from decorating specific url patterns?