Network setting in Ubuntu 9.04 is not easy

Install Ubuntu 9.04 on Acer Aspire 4520 notebook is so easy and the Gnome X window so beautiful.
But the problem is setting up network like wireless and Mobile using Samsung SGH-L700 as 3G modem never success.
Wireless using Atheros (ath5k) sometimes work, but on the other time that configuration will be disappear. I must resetting the wireless. Huh .. so tired.
Samsung SGH-L700 as modem is never connect, the phone will be restart Immediately and then no response from the phone. Using wvdial not help too.
Only one connection is success that is ethernet. But I don't like using this connection now.
I guess this distro is not fully compatible for Aspire 4520.