Problems with NM seeing 3G modem

[<tcwalker san rr com>]

Hello, I am a new user to Linux and tried to find the proper resources before seeking help.

I am using NM 0.7.0-lp.0025.o.4
I am using a Sierra Wireless 881 WCDMA modem with ATT

As far as I can tell, I successfully installed the modem driver and it is listed as /dev/ttyUSB0

Unfortunately, when try to dial using wvdial, it says the device is busy.  So I can't verify that it is working.

Secondarily, if I open the NM window, I am only able to add a wired or WiFi connection.  So I'm not sure why I can't add the 3G device that the docs refer to.

I'm happy to read more, so if there is an existing FAQ that will help, please point me in that direction.

I am using this as my baseline:

http://www.sierrawireless.com/faq/ShowFAQ.aspx?ID=1076

Thank you!