function validate_form()
{var Doc = document.form1
 var test
	if(Doc.sender_name.value=="" || Doc.email.value=="" || Doc.message.value=="")
	{
		alert("Fields marked with (*) sign are required.")
		return false;
		test="failed";	
	}
	else
		{
		emailStr = Doc.email.value
		var emailPat=/^(.+)@(.+)$/
		var specialChars="\\(\\)<>@,;:\\\\\\\"\\.\\[\\]"
		var validChars="\[^\\s" + specialChars + "\]"
		var quotedUser="(\"[^\"]*\")"
		var ipDomainPat=/^\[(\d{1,3})\.(\d{1,3})\.(\d{1,3})\.(\d{1,3})\]$/
		var atom=validChars + '+'
		var word="(" + atom + "|" + quotedUser + ")"
		var userPat=new RegExp("^" + word + "(\\." + word + ")*$")
		var domainPat=new RegExp("^" + atom + "(\\." + atom +")*$")

		var matchArray=emailStr.match(emailPat)
		if (matchArray==null) {
			alert("Email address seems incorrect (check @ and .'s)")
			return false
			test="failed";
		}
		var user=matchArray[1]
		var domain=matchArray[2]

		// Domain is symbolic name
		var domainArray=domain.match(domainPat)
		if (domainArray==null) {
			alert("Email address seems incorrect (check @ and .'s)")
    		return false
			test="failed";
		}

		var atomPat=new RegExp(atom,"g")
		var domArr=domain.match(atomPat)
		var len=domArr.length
		if (domArr[domArr.length-1].length<2 || 
    		domArr[domArr.length-1].length>3) {
   			// the address must end in a two letter or three letter word.
  		 	alert("The address must end in a three-letter domain, or two letter country.")
   			return false
   			test="failed";
		}

			// Make sure there's a host name preceding the domain.
		if (len<2) {
   		var errStr="This address is missing a hostname!"
   		alert(errStr)
   		return false
   		test="failed";
		}
		else
		{
			Doc.submit()
		}
		}
}