Upgrading Jquery Mobile 1.2.0 to 1.4.5

Upgrading Jquery Mobile 1.2.0 to 1.4.5

Hi Friends,

I am upgrading my jquery mobile project from 1.2.0 to 1.4.5, but few css classes used in 1.2.0 are not working in 1.4.5. and our own custom css classes are also not applying.

Eg: ui-icon-arrow-l . Back arrow is not displaying.(This was available in 1.2.0)

Below is the order in which our css files are added to page after upgrading to 1.4.5

csscollection.Add("Content/jquery.mobile.theme.support.1.2.0.css");
csscollection.Add("Content/mobile.css");
csscollection.Add("Content/admin.css");
csscollection.Add("Content/jquery.mobile.icons.min.css");
csscollection.Add("Content/jquery.mobile.structure-1.4.5.css");
csscollection.Add("Content/jquery.mobile-1.4.5.css");

query.mobile.theme.support.1.2.0.css is build from theme roller website from the theme available in jquery 1.2.0

Following is the old order 

csscollection.Add("Content/jquery.mobile-1.2.0.min.css");
csscollection.Add("Content/mobile.css");
csscollection.Add("Content/admin.css");

Please help me to achieve my existing css work in new css.