Adding parameter to user profile with SUSR_USER_PARAMETERS_PUT

I have problems adding a parameter to a user profile, i make use of FM SUSR_USER_PARAMETERS_PUT.

sy-subrc = 0 but no parameter is added (not showing this parameter in SU01).

when i add the parameter manualy it is not shown in FM SUSR_USER_PARAMETERS_GET.

Do i use wrong FM????

***********************CODE****************************************

DATA: lt_user_parameters TYPE TABLE OF usparam,

lw_user_parameters LIKE LINE OF lt_user_parameters.

lw_user_parameters-parid = 'CATS_APPR_PROF'.

lw_user_parameters-parva = 'AM-LINE'.

APPEND lw_user_parameters TO lt_user_parameters.

CALL FUNCTION 'SUSR_USER_PARAMETERS_PUT'

EXPORTING

user_name = 'TYPE A PROFILE'

TABLES

user_parameters = lt_user_parameters

EXCEPTIONS

user_name_not_exist = 1

OTHERS = 2.

Edited by: Richard van Veen on Nov 18, 2008 2:24 PM