Lots of errors on my forum. please help anyone

[semaster]

Hi,
I had several errors on my vbulletin forum.
Then i decided to upgrade my forum from 4.2.1 to 4.2.2

And now i see these errors in middle of every page of my forum :

vBulletin Message
Unable to add cookies, header already sent.
File: /home4/abc/public_html/includes/class_core.php
Line: 5755

And i see these errors on top of every page :

Warning: Non-static method VBCREDITS::user() should not be called statically in ..../includes/functions.php(1851) : eval()'d code on line 1

Warning: Non-static method VBCREDITS::templates() should not be called statically, assuming $this from incompatible context in ..../includes/class_bootstrap.php(1419) : eval()'d code on line 2

Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at ..../includes/class_core.php:5755) in ..../includes/facebook/facebook.php on line 49

Warning: Non-static method VBCREDITS::verify() should not be called statically, assuming $this from incompatible context in ..../includes/class_bootstrap.php(430) : eval()'d code on line 1

Warning: Non-static method VBCREDITS:rocess() should not be called statically, assuming $this from incompatible context in ..../dbtech/credits/credits_core.php on line 72

Warning: Non-static method VBCREDITS::init() should not be called statically, assuming $this from incompatible context in ..../dbtech/credits/credits_core.php on line 94

Warning: Only variables should be passed by reference in ..../includes/class_bootstrap.php(561) : eval()'d code on line 434

Warning: Only variables should be passed by reference in ..../includes/class_bootstrap.php(561) : eval()'d code on line 434

Warning: Non-static method VBCREDITS_VBULLETIN::navtabs() should not be called statically in ..../includes/functions_navigation.php(826) : eval()'d code on line 1

I upgraded to 4.2.2 but still new upgrade has not helped me and these errors are coming again and again.

Vbulletin.org has helped me each time when i had any problems with my forum. I am sure that this time also you people will help me.

Please help guys.