[Plugin: WordPress Special Characters in Usernames] Error on login request

Warning: session_start() [function.session-start]: open(/var/chroot/home/content/86/9513386/tmp/sess_8f0vgntpqtmd5dei8507388785, O_RDWR) failed: No such file or directory (2) in /home/content/86/9513386/html/gamerspost/wp-content/plugins/wordpress-social-login/authenticate.php on line 2

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /home/content/86/9513386/html/gamerspost/wp-content/plugins/wordpress-social-login/authenticate.php:2) in /home/content/86/9513386/html/gamerspost/wp-content/plugins/wordpress-social-login/authenticate.php on line 2

How can i solve it?

http://wordpress.org/extend/plugins/wordpress-special-characters-in-usernames/