I too am facing the same problem. I installed sp3 on this server. I received an interesting description
DATE/TIME: 1/17/2009 7:42:12 PM
DESCRIPTION: The SQL Server performance counter 'Buffer cache hit ratio' (instance 'N/A') of object 'MSSQL$I02:Buffer Manager' is now below the threshold of 99.00 (the current value is 1.00).
JOB RUN: (None)
The performance counter is not below 99.8, and I have set the mail to fire only when the figure goes below 99.
I changed it to run when hit ration raise above 1, but it never sent an alert . :w00t: