Huawei mobile broadband E173 data card not working properly

I am using Mac OS X SnowLeopard. My Huawei mobile broadband E173 data card is giving me problems. After inactivity for some time, it gets disconnected and when I connect again, it shows as connected but sites don't get loaded. Even the default startup page that's supposed to start on connection is not able to load. I am using the default driver that came with the device. Are there any alternative drivers?