user exit while vendor master creation

Deal All,

We have one requirement for whcih user exit might be required.

We are having a internal number range for Vendor master. As in internal number range system automatically generates Vendor master number.

Our requirement is whenever we create and save the vendor master, while saving system should copy the vendor number created into the field "Previos account no. in Vendor master.

Please reply

Thanks in advance

Vijay