Problem with Internet connection

view story

http://askubuntu.com – I have Windows Vista and 12.04 on my Dell D630 laptop. I'm using Huawei MT882 modem. I have installed Ubuntu two days ago using WUBI. I have tried with USB or ADSL cable but on Ubuntu, Internet connection won't work. On Windows however, it works perfectly (both USB and ADSL cable). Is there any way to fix this problem? Output of ifconfig: eth0 Link encap:Ethernet HWaddr 00:1c:23:0c:c5:cc UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 (HowTos)