isi there any difference between module controller and include controller

[Ravi Kiran]

hi,

       In our test plan we have the following things.

ForEach Controller 1
  --> ForEach controller 2   (Inside for each controller 1)
       -->if controller 1          (Inside for each Controller 2)
       -->if controller 2          (Inside for each Controller 2)
       -->if controoler 3         (Inside for each Controller 2)
       -->Module controller    (Inside for each Controller 2)    thats again 
goes to the For EachController1

But the thing is the test is running only if i delete the module controller.And 
the message that comes if i try to run including the module controller in the 
test plan is :
at 
org.apache.jmeter.guiaction.AbstractAction.converterSubTree<AbstractAction.java:69>

Is anything wrong with the test plan or module controller has any limitation?

Thanks In Advance
kiran