version:8.2.6 pg_hda.conf problem

Hi Everybody,
    I started running 8.2.6 recently on redhat 5.0 es,  installed pgadmin3  and phppgadmin ,both them can correct
connectby localhost,but can not from other , I had these in my pd_hda.conf : 

host  all  all  192.168.2.1/254 trust

and  listen_address=*   in postgresql.conf, but it still not work .

ps: I can not find tcpip_  ...in  postgresql.conf.

how can i do now ?

ths a lot!

leekooqi