[ILUG-BOM] how do i use kppp with an external modem

i have borrowed an external d-link modem, which i've configured thru wvdial (thanx 4 answering my previous mail 2 help me do that) when i try 2 use kppp, it says "sorry, can't open modem"

how do i configure the modem (d-link dfm 560-e (external)) in kppp. also i was able 2 configure my internal modem thru kppp in rhl 7.1 but every time i ran kppp, it asked me for the root passwd. i tried changing the access permissions of /usr/bin/kppp & also /usr/sbin/kppp to 777, but it did not make the problem go. b'coz of the need 2 provide the root passwd every time it is reqd 2 connect 2 the net, i can't have my younger brother access the net thru linux