How do I make my email contact form work on Yahoo hosting?

I am using PHP mail() function to receive information from customer. (contact form)
It is not working. I also checked spam folder..
I tested the same form using 3 other web hosts. It works fine on other hosts.
What should I do to make php mail function work on Yahoo?

Sorry for the trouble,

Yahoo! Web Hosting uses our own Sendmail program for PHP-driven email. For information regarding PHP mail forms, you can check out help.yahoo.com//l/us/yahoo/smallbus...

Yahoo! Web Hosting also uses a built in form script that can be generated by the instructions at help.yahoo.com//l/us/yahoo/smallbus...

If you have any questions about either of these features, contact us anytime at smallbusiness.yahoo.com/contactus