Problems with OpenID plugin

Hello,

I’m actually having problems with plugin “External Identities – OpenID”.

I turn it on, and when a user comes to login with it, he type his password on the OpenID server and, later, show this:

is_valid:true
Warning: Cannot modify header information - headers already sent by (output started at /home/x/wp-content/plugins/exid/class.openid.php:311) in /home/x/wp-includes/pluggable.php on line 492

Warning: Cannot modify header information - headers already sent by (output started at /home/x/wp-content/plugins/exid/class.openid.php:311) in /home/x/wp-includes/pluggable.php on line 493

Warning: Cannot modify header information - headers already sent by (output started at /home/x/wp-content/plugins/exid/class.openid.php:311) in /home/x/wp-includes/pluggable.php on line 494

Warning: Cannot modify header information - headers already sent by (output started at /home/x/wp-content/plugins/exid/class.openid.php:311) in /home/x/wp-includes/pluggable.php on line 495

Warning: Cannot modify header information - headers already sent by (output started at /home/x/wp-content/plugins/exid/class.openid.php:311) in /home/x/wp-includes/pluggable.php on line 480

Warning: Cannot modify header information - headers already sent by (output started at /home/x/wp-content/plugins/exid/class.openid.php:311) in /home/x/wp-includes/pluggable.php on line 481

Warning: Cannot modify header information - headers already sent by (output started at /home/x/wp-content/plugins/exid/class.openid.php:311) in /home/x/wp-content/plugins/exid/ExternalIdentities-OpenID.php on line 93

How can I fix this? Do you know another plugin that can have the same function?

Thanks!