Internal pages show desktop theme

Joomla Version; 1.5.26

I installed the component for the domain heightsglobal.com .
It showed the home page in the mobile template, but when i clicked on the link, it showed the page in the desktop version.
But after some time, when I again checked the site on the mobile (android), it shows the desktop version.

What has to be done to show the mobile version.

Joomla version 2.5.4

I installed mobile joomla and it works well immediatly on my HTC Desire. At this time, on my smartphone, I got some links as "mobile version" and "standard version" . I tried to click on "standard version" and from this time, i get only the desktop version and I does'nt find any way to return to the mobile version. What has to be done to get again the mobile version ?

Hi, my previous message was probably unuseful !! In fact I(d to clean the cookies of the smartphone and everything is OK now!
Sorry for the trouble !!

Hi, i clean my cookies, cache, historial, even passord everything and the internal pages dosen´t show up... i´m from Venezuela, sorry for the mistakes.