I think what you're asking for is a locale time in GMT+5.
Given an ISO timestamp, 1325233011
When I convert this to a locale-based date/time
Time.at(1325233011) => '2011-12-30 03:16:51 -0500'
Take a look at the ruby-docs, http://www.ruby-doc.org/core-1.9.3/Time.html for more information. Ruby has robust Time and Date classes with many helper utilities. My machine is configured for GMT-5 so it returns the local time. It's easy to change the way timezone settings are interpreted in your program, but that's for another day. Hope this helps!