// validate contact form function
function validate() {
		var form = document.forms['contact_form'];
		var i;
		var errorMessage = '';
	
// check format of phone_number!
		var count=0;
   	 	for (i = 0; i < form.phone_number.value.length; i++){   
        	var c = form.phone_number.value.charAt(i);
       		if ((c < "0") || (c > "9")){
				if (c!="-"){ 
					count=0; // set to zero to account for the break, meaning a letter!
					{break}
				}
				count-=1; // minuses 1 from count to account for the dash!
			}
			count+=1;		
   		}
		if(count != 10) // phone number should have 10 numbers
			errorMessage = errorMessage + 'Please enter a valid phone number.\n';	

// check format of email_address !
		if(form.email_address.value == ''){ 
			errorMessage = errorMessage + 'Please enter a valid email address.\n';
		}else{
			apos=form.email_address.value.indexOf("@")
			dotpos=form.email_address.value.lastIndexOf(".")
				if (apos<1||dotpos-apos<2) 
					errorMessage = errorMessage + 'Please enter a valid email address.\n';
		}
		
// check message
		if(form.message.value == ''){ 
			errorMessage = errorMessage + 'Please enter a message.\n';
		}

// display alert or submit
		if(errorMessage != "") {
			alert(errorMessage);
		} else {
			form.submit();
		}
		errorMessage = "";
}