User Exit while saving the Excise Invoice in J1IIN

Dear All,

I want know whether anu User Exits are there while saving the Excise Invoice in J1IIN.

The "scenario" here is as follows:

---I will create an invoice(Commercial) in VF01. Suppose I got a number 1234(This is Billing Document number).

---Now I will go to J1IIN and create an Excise Invoice by reffering to the VF01 Billing Doc Number.I will enter all the details. Then I will Save it. While saving I want to check the following aspect:

I want to compare the Billing Document Number and Excise Invoice Number and give error if both the numbers are not same.

---That is I want to see that Excise Invoice and Billng Document number should be same.

I need your suggestion in the above scenario.

I will definitely reward if problem is solved.

Regards,

Raj Kumar Reddy.