Multiple Ship to Party( 999) ,Partner Determination

Question

Due to the 999 entry restriction we cannot maintain more than 999 ship to party in the sold to customer master data, to overcome this problem we have implemented a workaround, We don’t maintain the ship to party in the sold to party customer data , but we maintain the sold to party in the Ship to customer master data. Hence while entering the Sales order, business is supposed to enter the ship to party field and we expect the sold to party to be determined. This doesn’t happen in the standard way so our plan is to use the partner determination user exit to get the Sold to party master data. I understand that in order to use the partner determination user exit EXIT_SAPLV09A_003 we need to make some changes in the configuration of partner determination procedure as well (source X, Y or Z in partner determination procedure, transaction VOPA). Is there any other changes required which needs to be done. Has any one implemented something like this? Will this work? Any help in this regards highly appreciated.
Regards,
Ankur Bhandari

Answer 1

Normally while maintaining the customer master we maintain
1.)    Sold to party as A
2.)    Ship to party as B
3.)    Payer as           C
4.)    Bill to party as   D
But we have more than 999 Ship to parties, hence we cannot maintain the ship to entries.
1.)    Sold to party as A
2.)    Payer as           C
3.)    Bill to party as   D
<b>5.)   Ship to party as B1
6.)   Ship to party as B2
7.)   …                     B999</b>
Hence we thought of maintaining the Sold to party in the customer master data of B1 like below.
1.)    Ship to party B1
2.)    Sold to party A
1.)    Ship to party B2.
2.)    Sold to party A.
1.)    Ship to party B999.
2.)    Sold to party A.
Now whenever the user enters B1-B999 in the ship to party in Sales Order creation , we want the corresponding Sold to party be retrieved as A, as per my understanding the user exit to do this is EXIT_SAPLV09A_003, but when I activate this userexit and enter the ship to party the code never reaches this exit and instead throws an error “Ship to party is B1 is not assigned to a sold to party”, which is incorrect as I have assigned the sold to party in Ship to parties master data.
Is my approach correct approach or should I be considering some other alternative. Please advise.