Jobs do not run properly and restores do not work because infrastructure is currently on vSphere 5.
VDDK API calls used by Veeam Backup & Replication 5.x do not support vSphere 5.
Contact support at http://www.veeam.com/support-form.html and place a ticket requesting a patch for vSphere 5. Also, make sure that you are using the latest version of Veeam Backup & Replication, and that no jobs are running during the patching process. The latest version of Veeam Backup & Replication is 5.0.2.230.
After patching, the version of Veeam Backup & Replication will not change (it will be 5.0.2.230), and you will not notice any difference in the GUI.
UPDATE:
If you have previously applied for the vSphere 5 patch, and are experiencing higher than normal CPU and/or drop in performance rates, please contact Support for an updated patch.
(This applies to cases when the patch had been applied prior to November 3, 2011.)