[Mono-aspnet-list] Trace.axd not working

[APS]

Hi, I downloaded 2.4.2.3 vmware machine and I installed my web 
application to test it with the new version.
I'm not able to enable tracing. I set

<trace enabled="true" requestLimit="20" pageOutput="false" 
traceMode="SortByTime" localOnly="false" />

in web.config but it still say:

HTTP 500. Trace.axd is not enabled in the configuration file for this 
application.

Same application with the same configuration in 2.0.1 works well.
I'm doing something wrong?