How can i send a message to perticular workflow

Hi Workflow Experts,

I have a urgent requirement, i.e i need to compare delivery level and order level dates and quantity...i am comparing these diff. in a user exit. If i find any diff. in dates and quantity then i have to send a message ( There is diff. quantity in order and delivery ) to a workflow.

Please any body help me out, how can i do this task. Is there any FM to send a message to a perticular workflow.

Thanks in advacne,

Ramesh.