Cron Job Error At 12:00 for All 5 sites

Since Wed until today, every 12:00 A.M I got emails regarding cron job errors in all of my 5 Dolphin sites. The error is:

2013-09-27 00:00:18 cwd=/home/mysite/public_html/mysite.com/periodic 4 args: /usr/sbin/sendmail -t -i -FmyEmail@yahoo.com 

I check the email for my cron job is MyEmail@yahoo.com  in Cpanel, but somehow there's an extra F included in the error above.

5 sites? All of them?

First thing i would do would be to contact the host. They must have changed something.

 yes, 1 same error for all 5 sites.