Networking :: how to configure modem gprs usb?

Hi to all, i'm new of forum and excuse me for bad english...
My problem is a modem gprs usb (Telit-Motorola),
DSL with the command "dmesg" report me is a "ttyACM0" right, but in the wizard of PPP dialup config, the choises are only "ttySx".
I tried manually to digit ttyACM0, but DSL not connect, at the end of the log i have "...no running network protocols.."
I have DSL 0.9.xxx on the HD already installed.
Thanks for helps

original here.