So you've got an Australian Virgin Mobile Broadband SIM and a 3G modem and you want to make it work in Linux? Well you're in luck! Please note: these settings will work on Fedora/RedHat/CentOS distros and should work on Debian/Ubuntu and other variants, but I've only tested on Fedora 13/14.
First off, you will need to add or edit a Mobile Broadband connection. To do that you need to get to the "Network Connections" dialog; go to System->Preferences->Network Connections or right click your NetworkManager icon and go to "Edit Connections..." - this will vary depending on your distro. Once there, select the "Mobile Broadband" tab and edit or create a connection named "Virgin Mobile Broadband".
Now onto the settings:
Mobile Broadband tab
- Number: *99#
- APN: VirginBroadband
PPP Settings tab
- Allowed auth methods: Select PAP only
IPv4 Settings tab
- Method: Automatic (PPP)