USB Modem disconnection and loading page issue in 12.04

Question

I have a Huawei USB dongle E173

$ lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 005 Device 002: ID 045e:0084 Microsoft Corp. Basic Optical Mouse
Bus 001 Device 006: ID 12d1:1436 Huawei Technologies Co., Ltd.

In Disk Utility, I can see Huawei SD Storage and Cd drive (I hope this is the modem). I can connect to Internet with speed of 160Kbps.

The problem is

1. After connecting, sometimes pages doesn't load and I have to load it again and again to display page.

2. After 1 and a half hour, the modem gets disconnected and to reconnect, I have to physically unlpug and plug the USB.

I tried WVDIAL and usbmodswitch but no help.