urgent: how to add additional records to hashed table

Hi,

I want to add records to a hashed table.

my code is:

data: ipn_pc_zoba type hashed table of tpn_pc_zoba with unique key vbeln.

loop at izoba into wzoba.

clear wpn_pc_zoba .

read table ipn_pc_zoba into wpn_pc_zoba with key vbeln = wzoba-LS_KDAUF.

if sy-subrc ne 0.

wpn_pc_zoba-vbeln = wzoba-LS_KDAUF.

append wpn_pc_zoba to ipn_pc_zoba.

endif.

endloop.

The Error is : You cannot use explicit or implicit index operations on tables with types "HASHED TABLE" or "ANY TABLE". "IPN_PC_ZOBA" has the type "HASHED TABLE". It is possible that .

How to solve this?

Please reply ASAP.

Regards,

SRI