Send mail to multiple users

[Workflow Icmitalia]

Hi all,
I'm developing a workflow on purchase requisitions based on single item-wise.
I have the following problem:
I copied workflow template 00000038, the responsibles for releasing the
requistion are identified by role 148; now if no one of the selected agents
executed the workitem in his inbox and a deadline event is triggered, I want to
send a text mail to all selected agents identified in the previous task.
Unfortunately in  the subsequent "send-mail" task (background task)I can't
identify how to bind these information, I only can send a mail to the
Workflow-initiatior.
 
Thank a lot for your suggestions,
Fabrizio