warning: unserialize() expects parameter 1 to be string, array given in /home/wilsonng/public_html/npaxcorp/modules/localizer/mo

Please help me out on this error. "warning: unserialize() expects parameter 1 to be string, array given in /home/wilsonng/public_html/npaxcorp/modules/localizer/modules/localizernode.module on line 272."
Take a visit on our site www.n-pax.net and navigate to every pages of it and you'll see that this error message appear to all navigations. I don't know what went wrong its just so abrupt that this error happened. Also, I wanted to log in to the site to administer it but it will just logged out. Please help me guys.. I'll be waiting for your replies...Thanks.......