Dynpro: PROCESS ON VALUE-REQUEST: with FIELD and module

Hello,

I have a problem with dynpro-programming:

This is the coding on my dynpro:

PROCESS ON VALUE-REQUEST.

   FIELD zmepo_badi_9000-ateil
   MODULE suchhilfe_ateil.

At the dynpro there are two fields: ateil and kstar

In Module suchhilfe_ateil I want to get back the value of  zmepo_badi_9000-ateil and
zmepo_badi_9000-kstar. In suchhilfe_ateil I`m using the FB 
F4IF_INT_TABLE_VALUE_REQUEST to get a F4 help.

I both fields on Dynpro are empty there is no problem: both fields get filled.

But when the Dynpro is filled and I want to change it with the help of F4, the value of kstar doesn`t change. It`s still the same as before.

It only works if kstar is empty. Then the correct value gets in the correct field.

Here is a part of the coding of    MODULE suchhilfe_ateil:

            zmepo_badi_9000-z_kstar     = lv_kstar.
            zmepo_badi_9000-ateil       = lv_ateil.

*           "Setze Enter
            CALL FUNCTION 'SAPGUI_SET_FUNCTIONCODE'
              EXPORTING
                functioncode           = '/00'
              EXCEPTIONS
                function_not_supported = 1.

in lv_kstar is the correct value, but on the dynpro it does not change.

I hope anybody can help me!

Thank you.