As tz1 said, if the device takes more current, you would need to use a powered hub in between.
With the device in host mode, you can try these steps out

You would need to know the device vendorid and product id by doing a cat /proc/bus/usb/devices

You can get the usbserial.ko from the thread below
http://www.internettablettalk.com/fo...ad.php?t=14877

sudo modprobe usbserial vendor=0x5c6 product=0x6000;

try the link below for more details on setting up pppd for dialing out
http://www.linux.com/feature/52729?theme=print

Let us know if you can make some progress.