connection failed

[gamalt tant <gamalt2 yahoo com>]

i was try to connect to the internet throu ext serial
us robotics on redhat8.0. the modem dialed the number
then i get error message 
"could not find ppp0 interface"
"the pppd died unexpectedly:"
exit status 19.
how can i fix this problem?

                     thanks

__________________________________
Do you Yahoo!?
The New Yahoo! Shopping - with improved product search
http://shopping.yahoo.com