Email Notifications after reaching the desired size of my Tablespace:

Hi..,
What I 've to do, if I want to get an email notification, after my Tablespace(it is not set the autoextend on) is reached the desired size.
Through OEM, I've seen an option i.e "Thresholds" Database -->Administration-->Storage-->Tablespaces-->Tablespace Name-->DataFile Name-->Tablespace Name-->Thresholds Tab-->Specified Thresholds.
With this can I get the email Notification..?
If not then what is this and how can I get the email notifications..?
If yes, I 've tried but, there is no result, I've configured my SMTP well, am getting the mails through my database..)

You can get mails using OEM just set it up correctly