Warning: join() [function.join]: Invalid arguments passed post-template.php

Hi,
I am getting below error message on any template on my website –

wordpress version – 3.9.1

gopaldas.org – going to any post or any other page, http://gopaldas.org/spring/spring-aop-vs-aspectj-comparison/

Warning: join() [function.join]: Invalid arguments passed in /home/content/27/12194627/html/wp-includes/post-template.php on line 478
class=””>

please help.