Mobile joomla displaying just at typing IP address

Hi, I am using Mobile Joomla with Joomla 2.5.

My problem is that the "mobile display" is  shown when writing in the browser the IP address of my server, and when I type the DNS it shows always the full site normal template.

I had wrote in joomla configuration.php this way: public $live_site = '';
If I write the name in joomla configuration.php, the component shows error and the joomla system do not work, so I didn´t use a name there.

I had wrote in MobileJoomla Domain name the DNS of my site and try changing it to the IP address, nothing working.

So I hope you can help me to know what am I doing wrong...   

Tks so much in advance!!

Do you use subdomain for mobile version? If you don't, set domain name empty.

I tried that, but when I erased the info in the Domain field in Mobil Joomla component and then saved it, the system keeps showing my domain name, www....