That's a feature of the server. Your LG tells it's an LG, not a Windows PC running IE9, so their server decides to show you the mobile version. Ain't that a nice feature of webservers and websites that they can be programmed to take the "agent" into account?

Now go and complain with twitters custome service about this. Their website (at least the Dutch version I see) says "feel free to contact us".

Kees