Last week, I bought bsnl evdo (zte). I am in bangalore, India. Internet is very very slow here. even I set my gmail to basic html mode.
I am assuming this is a 3G USB 'dongle'.
It's difficult to say, because you haven't told us what kind of signal strength you're getting. Assuming you have a weak signal, your time/money would be better spent trying to optimize your setup. Try using a longer USB cable to get better elevation, or at least to position your dongle where you can get a better signal.
This sounds like a Ubuntu (Linux) issue.
I also use Ubuntu as well as XP, and some versions of Ubuntu do not perform as well with wireless (signal strength wise).
Also the fact Firefox comes up offline indicates all is not well with your setup.
Its a driver issue, and some things work better than others.
Try the Linux (Ubuntu) forum to see if they can help.
Rob
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