cannot connect cellphone through wifi

Hi !

I have a bsnl broadband connection and have a secured router connected to it .I can use internet via wifi in my laptop but unable to connect with my samsung galaxy s9003!! The phone detects the wifi but fails to connect.PLs help.
Bsnl broadband is dataone
Router is linksys wireless g 24ghz

Pls help !!!

(a)
connect in "AlwaysON" PPPoE mode adsl modem.
{( userId/PW entered/stored) in WAN page}
(b)
Enable dhcp ( In lan page)
(c)
Enable UpNp box if seen.
(d)
give details of adsl modem and wifi router.
Model/make/NUMBER
(e)
mention OS used.

Samsung phones have really very weired WLAN setting procedures!