workflow question regarding purchase orders AX 2012


I want to utilize the change management feature for purchase orders in Dynamics ax 2012.

I have managed to build a really simple workflow for that but now I want to expand the functionality a little more.

I want the workflow to check if some of the financial dimensions are filled in on the purchase order line.

If else the workflow should return the order to the originator for correction.

But when I set a validation for that in the review purchase order task it didn’t work I got an error message that I can’t edit the purchase order when it returned.

I get the error message " only a document in status rejected can be resubmitted for approval" although I have the alternative to choose re-submit in the action button.

does some one has an idea to set a workflow like this up?

Regards Johan