Trying to set up a laptop to use a USRobotics Model 5637 USB modem so a friend can use a dial-up Internet connection.

This person needs a graphical user interface so I thought that GNOME PPP would be good. However I have been trying to get it to work on my laptop and when it tries to connect I get the following error:

Carrier detected. Starting PPP immediately
Unable to run /usr/sbin/pppd
Check permissions, or specify a "PPPD Path" option in wvdial.conf

Below is the content of wvdial.conf
[Dialer Defaults]
New PPPD = yes
Stupid Mode = yes
Modem Thpe = Analog Modem
ISDN = 0
Auto DNS = 1
Auto Reconnect = 0
Modem = /dev/ttyACM0
Baud = 230400
Initl = ATZ4

Phone = 250 388 5747
Username = {name}
Password = {password}

Here is what the specs on on /usr/sbin/pppd :
Type is: executable,
permissions are: -rwxrwxr--
Owner:Group is: root:30 That looks odd to me but I am still pretty green with Ubuntu.

Can anyone suggest what I must change, and how to get this machine to connect to the Internet via dial-up using GNOME PPP or other graphical interface?