Cursor position problem in LM03/LM05

Hi SAP Gurus,

We have created a new sub screen to include Batch field in the LM03 and LM05, by using user exits EXIT_SAPLLMOB_170,EXIT_SAPLLMOB_480.

the logic is working for validation of batch while doing the transaction, but problem is cursor is not moving from one field to another field automatically,

please suggest what are the settings and modifications to be done in logic and configuration, to move the cursor automatically.

Thanks in advance,

Pavan kumar.