[RESOLVED] regular expression for multiple email address

[verN]

hi, i have the following regular expression working for a single email address however when sending emails the to field in the form can take two or more email address which are sepearted by ,(comma) but the regular expression does't work for this. hERE IT IS:

if (eregi ('^{[[:alnum:]][a-z0-9.-]*@[a-z0-9.-]+.[a-z]{2,4}$',} stripslashes(trim($POST['to'])))) {
}

THANKS, i have changed it to include a comma but it still doesn't work. HELP!