PURCHASE REQUISITION RELEASE WORKFLOW

["Schrader N., Claude (Enap Refinerías)]

PURCHASE REQUISITION RELEASE WORKFLOW

PARALEL RESPONSIBLES WORKFLOW WORKS OK WITH HR RESSOURCE.
In SPRO > materials Management...  The "Release Strategy"  is defined with
only one "Release Code". The unique release code can be assigned to a
"Position"  in assigtnment of  role to release code(View=T16FW). 
With transaction PPOME, several responsible SAP USERS  can be assigned to
that  position. As the purchase requisition is created, all the responsibles
receive the some work-item in their workplace, as one of the responsibles
releases the requisition then the work-item  goes away from all the
workplace inboxes. In the interactive release workflow step, instead of
standard SAP rule 148 a custom rule defines the agents using the above
mentioned positions. It works fine.

What's the problem? :  - I am asked no to use HR ressources and to asociate
each agents SAP USER directly to its own relese code.
BUS2009.ReleaseStepCreated event is published oce for each release code
defined in the release strategy, no mater if the relese codes are to be
applied in sequence or only one is enough to unlock the requisition. After
the first agent releases the purchase requisition, then one work item is
kept in the workplace of each one of the other agents and I know no way to
eliminate those useless bloked work items.

Please Help me.
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