vb or server problem

[mofeu]

Dear all,

I change server on my forum and i have the following error message

Warning: session_start() [function.session-start]: open(/tmp/sess_b38ef99f0664e8e3dbe6a0a2aad9f532, O_RDWR) failed: Permission denied (13) in [path]/includes/facebook/facebook.php on line 37
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at [path]/includes/class_core.php:5615) in [path]/includes/facebook/facebook.php on line 37
Unable to add cookies, header already sent.
File: /home/mofeueu1/public_html/forum/includes/class_core.php
Line: 5615
Warning: Unknown: open(/tmp/sess_b38ef99f0664e8e3dbe6a0a2aad9f532, O_RDWR) failed: Permission denied (13) in Unknown on line 0
Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/tmp) in Unknown on line 0

To the old server , the vb was working.

Any idea?