Setup of Notification ActivityinWF forHoldsapplied

[naresh.apps11i]

Hi Apps Gurus,
Thank you for your answers to my earlier queries.

Client requirement is like as below;

The Client wants to have a Credit hold applied at the time of pick releasing the SO for certain customers depending upon their credit worthiness.When hold applied ,the same is to be notified to thier Sales dept Head and Financial dept head. This has to be incorporated in work flow.
How this can be incorporated in Work Flow.
Please explain me in detail in steps with navigation,

Earliest reply will be highly appreciated.

Thanks & Regards,
Naresh