how can I send a e-mail with the sender's address is my company's e-mail ???

Hi , My copmany have a website and is hosted on a web server of some web hosting company . I want to use PHP to send e-mail on that server . I use $result = mail("abc@foo.com" , "E-mail Test" , "this e-mail is sent by php") ; to do it . But when I receive the e-mail , the SENDER 's address is the server's domain name ! such as 'anonmyous@hostingserver.com' It's a large problem if I send a e-mail to my clients with this cos they won't know who send the e-mail !! how can I send a e-mail with the sender's address is my company's e-mail ??? for exmaple ' mycompany@company.com '?? THX A LOT