You want an ACD packafe which supports position in queue.

The product which replaced the Samsung ACD (forgotten the name of it) could do it.
It was made by a UK company.
Don't know if it's available in your region or not.
Otherwise you're looking for a 3rd party acd product compatible with the os7000.
Down here we have a company called cytrack which developed such a product. Even had it working with the scm too.