I thought we covered that. You won't be able to get that information in a third party application. Your line of inquiry is based on a false assumption. A Blackberry never connects or disconnects from the Internet (except when turning on/off or entering/leaving coverage). The browser never starts or stops except when the device reboots. You may (with a BES) easily find out what URLs a user looks at and when (unless you allow third party browsers).

If you really have to have that kind of data, you should probably put your users on a BES anyway. Once they are on a BES you can disable all browsers except the Desktop Browser, disable loading third party applications then buy web monitoring software for your network.