function validate_email(field,alerttxt) {
				with (field)
				{
					apos=value.indexOf("@");
					dotpos=value.lastIndexOf(".");
					if (apos<1||dotpos-apos<2) 
					  {alert(alerttxt);return false;}
					else {return true;}
				}
			}
				
			function checkform ( form )
			{
			
			  // ** START **
			  if (form.name.value == "") {
				alert( "Please enter your name." );
				form.name.focus();
				return false ;
			  }
			  if (form.company.value == "") {
				alert( "Please enter your company name." );
				form.company.focus();
				return false ;
			  } 
			  if (form.phone.value == "") {
				alert( "Please enter your phone number." );
				form.phone.focus();
				return false ;
			  } 
			  if (form.email.value == "") {
				alert( "Please enter your email address." );
				form.email.focus();
				return false ;
			  }   
			  if (validate_email(form.email,"Not a valid e-mail address!")==false) {
			  	form.email.focus();
				return false;
			  }  
			  // ** END **
			  return true ;
			}