Javascript Validation ready to use

<form name="contact" onsubmit="return verify(this)" action="formmail.php" method="post">

<script>

function isblank(s)
   {
     for(var i = 0; i < s.length; i++)
     {
       var c = s.charAt(i);
       if ((c != ' ') && (c != '\n') && (c != '\t')) return false;
     }
     return true;
   }

function verify(f)
   {
     var msg;
     var errors = "";
     var valemail = /^[\w-]+(\.[\w-]+)*@([\w-]+\.)+[a-zA-Z]{2,7}$/;
     var valphone = /\d{3}-\d{3}-\d{4}/;
 
     if (isblank(document.contact.email.value) && isblank(document.contact.phone.value))
       errors = "You must enter either your email address or your phone number.\n";
     if ((!isblank(document.contact.email.value)) && (!document.contact.email.value.match(valemail)))
       errors = "You must enter a valid email address (user@domain.name).\n";
     if ((!isblank(document.contact.phone.value)) && (!document.contact.phone.value.match(valphone)))
       errors = "You must enter a valid phone number (123-456-7890).\n";
     if (isblank(document.contact.comments.value))
       errors += "You did not enter any comments or requests.\n";
     if (!errors) {
       if (isblank(document.contact.email.value)) document.contact.email.value = "webmaster@pcvsoftware.net";
       return true;
     }
     msg = "______________________________________________________________\n\n";
     msg += "The form was not submitted because of the following error(s).\n";
     msg += "Please correct your entries and re-submit.\n";
     msg += "______________________________________________________________\n\n";
     msg += errors;
     alert(msg);
     return false;
   }</scirpt>