CRM MTO sales order in the R/3 System does not do a ATP check

Hi

CRM MTO sales order in the R/3 System does not do a ATP check.

If I create MTO sales order in the R/3 it will go for ATP check with same material and plant.

Any particular setting I need to make to allow CRM order for ATP check in R/3 so that I can create a delivery.

Thanks in advance.

Abhi