function checkme(f) {
	 var errors = [], 
	 i = 0, 
	 first = false, 
	 filter = /^([a-zA-Z0-9_\.\-])+\@(([a-zA-Z0-9\-])+\.)+([a-zA-Z0-9]{2,4})+$/, 
	 str = f.getAttribute("name").replace("_", " ");
	 
	 if(f["name"].value.length == 0) {
		errors.push("Please include your name");
		first = f["name"];
	 }

	 if(f["email"].value.length == 0 && f["telephone"].value.length == 0) {
		errors.push("Please enter your telephone or email address");
	 } else if(f["email"].value.length > 0 && !filter.test(f["email"].value)) {
		errors.push("Please include a valid email address");
		if(!first) {
			first = f["email"];
		}
	 }
	 
	 if(f["enquiry"].value.length == 0) {
		errors.push("Please enter your enquiry");
		if(!first) {
			 first = f["enquiry"];
		}
	 }
	 
	 if(f["address"].value.length == 0 || isNaN(f["address"].value)) {
		errors.push("Please complete the sum");
		if(!first) {
			first = f["address"];
		}
	 }

	 if(errors.length > 0) {
		var error_string = (errors.length == 1) ? "A problem was found with your "+ str +":" : "Problems were found with your "+ str +":";
		alert(error_string +"\n\n"+ errors.join("\n"));
		if(first != false) {
			first.focus();
		}
		return false;
	 }
	 return true;
}