printing mataerial description for batch split material at delivery level

Hi all,

Here i am printing the material description which is maintained in the item level at sales order level.For each material they have maintained two material descripption.I am not able to display the second material description in my export invoice whenever the material is splited into batch ie batch split at delivery level. so please can anyone help me regarding this, I am not able to get it from long time.

Regards,

madhu