Stack trace emulation for web mode in GWT

Question

In my development module, I have set the following properties:

<set-property name="compiler.emulatedStack" value="true"/>
<set-configuration-property name="compiler.emulatedStack.recordLineNumbers" value="true"/>
<set-configuration-property name="compiler.emulatedStack.recordFileNames" value="true"/>

but when running against the compiled GWT app, Firebug does not display a stack trace and it does not even halt on error. All I get is something similar to:

uncaught exception: java.lang.IndexOutOfBoundsException: Index: 0, Size: 0

Line 0

I am using GWT 2.0.1, Firefox 3.6.6 and FireBug 1.5.4 . The error console is not helpful either.

What should I do to get error stack traces in web mode?