Starting a workflow from an error message

[Nat 4 Govender]

Hi All,
 
I was wondering if any one of you could possible help me on this.
 
We have used transaction "SWUY" to link a workflow to an HR error message.
When we test the workflow using transaction "SWUS " by providing the
relevant parameters the workflow works however when testing the workflow
using a HR transaction and the error message appears but the workflow is
not triggered.
 
Does anyone know what's the problem.
 
 
 
(Embedded image moved to file: pic03902.jpg)