Oracle Forms

Hi Frds,

I have created a custom logon screen and its working fine.On logon trigger i used call_form to call a new form.you can see the code below.What i exactly want is i want to close this form and open a new form when successfully logged into database. I tried to keep new_form instead of call_form. but its not working. Please guide me with good solution asap friends.
***on-logon trigger***
declare
formFlag boolean;
begin
if :block3.userName is not null and :block3.password is not null then
logon(:block3.userName,:block3.passWord||'@'||'sptest',false);
formFlag := form_success;
if formFlag then
--replace_menu('pog_plan_menu');
call_form('pog_plan');
else
message('Invalid user/password. Please try again ');
end if;
end if;
end;
****login button.when button pressed***
logon(null,null,false);

Thanks in advance,
Vamsi.