Suppress Alert not working

Hi All,

I have configured Component based alerting as per below blog

http://scn.sap.com/community/pi-and-soa-middleware/blog/2012/03/25/michals-pi-tips-component-based-message-alerting

I have selected the Suppressing alerts and Aggregation Alerts option while configuring.

I am getting email for alerts but suppressing alerts is not working.

I am getting multiple mails for same error.

Any regarding this would be highly appreciated.

Regards,

Sudha