Triggerring Workflow when Purchase Requisition is Created(URGENT)

Hi Experts,

There is a requirement, where i have to trigger a Purchase Requisition workflow, when a PR is Created. I have used RELEASESTEPCREATED event, to trigger the workflow when a PR is created.

But there is a error, RELEASESTEPCREATED event is not getting triggered, when PR item is not having a Release Strategy.

Please suggest what can be done, in detail.

Thanks in Advance.

Kartikey.