Notify function in CVS

Hello, I want to use the notify function in the CVS (I'm using 1.10.8)

I add a watch (for commit action) for a file. Also, I uncomment the file named notify in the server's CVSROOT. The line I uncomment is like following:
ALL mail %s -s "CVS notification"

Then I use another person to login and commit changes to the file that watched by the first people. But the first people did not get the mail notification. Also, when the second people commit changes, an message like "mail: Options MUST PRECEDE persons" display.

Why?
How do I set the notify file to notify people when their watched files are changed. Also, in the mail, I 'd like to include the the changed filename.

Thanks.