php session variable value is null when hosted to server
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i having a strange issue in sessions.. this is working in WAMP server in my local machine.. my problem is wen hosted to a server in US it's not working..

im doing like this..

session_start();
$_SESSION['test'] = 'testing login..';

in another page i'm doing..

session_start();
echo('my session value is : '.$_SESSION['test']);

but i'm getting only
my session value is : 

my session value is not setting..

i checked the session.save_path in cPanel of the server it says /tmp.

pls help.. 
thanks in advance