Search help description field is not updated right after the item selection

Hi,

In our SAP CRM system there is a search help, extended by function module (Z* user function). Everything works fine, except one thing — when user clicks on search help icon, default search help popup displayed, user can choose there an item, popup disappears and in ID textbox we can see the ID of selected item (it's OK), but the content of description field of this ID field is not updated. In order to update this value user must press «Enter» again on focused ID field or call search help popup again.

Example:

Originally we have «1 — Coca-Cola», now user clicks on search help with available drinks and choose «2 — Pepsi», pop up disappears, user sees: «2 — Coca-Cola», instead of «2 — Pepsi» and only after second press on «Enter» user gets the updated value of description field — «2 — Pepsi».

All search help extension function code is placed inside of the following IF validation statement:

1. IF callcontrol-step ='SELECT'.
2. ENDIF.

and one line before exit from the user extension function there is update of callcontrol-step parameter:

1. callcontrol-step ='DISP'.

So, why the value is not updated immediately upon the selection in search help popup?

How to make update description field upon the item selection in search help?

Thanks.