Event ID 208, Source SQLSERVERAGENT

Good morning all,

I am getting the following error reported on one of the SQL servers, I have reported this problem to the SQL DBA but he is blaming it on the backup software.  I can't see this myself and as I don't have any SQL expiriance except installing could someone shed some like on this so I get my DBA to fix the problem.

Source: SQLSERVERAGENT
Time: 01:00:00
Event: 208
Description
SQL Server Scheduled Job "Integrity Checks Jobs for DB Maintenance Plan 'ASDB Maintenance Plan"
(0x97B8CCF5E8AC1840BA789B2E-45488528) - Status: Failed - Invoked on 2008-09-02 01:00:00 - Message: The job failed.  The owner () of job Integrity Checks Job for DB Maintenance Plan 'ASDB Maintenance Plan' does not have server access

Source: SQLSERVERAGENT
Time: 01:15:00
Event: 208
Description
SQL Server Scheduled Job "Optimizations Jobs for DB Maintenance Plan 'ASDB Maintenance Plan"
(0x9F21CF5D6160AC498CC6BAFEF2BCB8DA) - Status: Failed - Invoked on 2008-09-02 01:15:00 - Message: The job failed.  The owner () of job Optimizations Job for DB Maintenance Plan 'ASDB Maintenance Plan' does not have server access

These errors started last week when I deleted an user account of someone who left the company quite a while ago.

Thanks for your help.