Work Item text not getting contents of variable

[Robin Sahasranam]

I am building a simple  workflow template (4.0b) to notify the creator of a
requisition when the requisition is released by the manager. The workflow has a
single-step foreground task. The work-item text uses the variable
&_WORKITEM.WORKITEMFATHER.CREATEDBYUSER.NAME& to display the name of the manager
who approved the equisition. I also use the same variable in the long text
description.
 
At run time the task is created correctly, except that the above variable does
not get the contents in the WorkItem text but does get the correct value in the
long text.
 
e.g.
 
The WI text shows :   Requisition 12345 released by
&_WORKITEM.WORKITEMFATHER.CREATEDBYUSER.NAME&
The long text shows:  Requisition 12345 released by John Doe.
 
Thanks in advance for any help you can offer.
 
Robin Sahasranam
World Bank