possible badi instead of cmod for bex variables?

We want use badi enhancement for bex variables istead of customer exit.

We used RSROA_VARIABLES_EXIT for this and created /FITGL/VAR_EXIT_GUEBG implemantation.

We use this badi for  /FITGL/GUEBG infoobject.

Just simple query for to get current date to ZENTRYDATE variable.

Here is the code;

METHOD if_rsroa_variables_exit_badi~process.
*    c_s_customer-vproctp = 1.

CASE i_vnam.

WHEN 'ZENTRYDATE'.

DATA l_s_range TYPE rrrangesid.

IF i_step = 1.
l_s_range-low = sy-datum.
l_s_range-sign = 'I'.
l_s_range-opt = 'EQ'.
APPEND l_s_range TO c_t_range.


ENDIF.

ENDCASE.


ENDMETHOD.

But code doesnt work..we debugged code and noticed that,code goes to ZXRSRU01 at the end.but nothing in there and ZENTRYDATE becomes null.

is there a way to using just badi for bex variables.