function findPosY(obj) {
			var curtop = 0;
			if (obj.offsetParent) {
				while (obj.offsetParent) {
					curtop += obj.offsetTop
					obj = obj.offsetParent;
				}
			} else if (obj.y) {
				curtop += obj.y;
			}
			
			return curtop;
			
		}
		
		function formCheck(formobj) {
			// name of mandatory fields
			checkAll = false;
			var fieldRequired = Array("name", "initials", "sex", "address", "postal", "city", "telephone");
			// field description to appear in the dialog box
			var fieldDescription = Array("Uw naam", "Voorletters", "Geslacht", "Adres", "Postcode", "Plaats", "Telefoon");
			// dialog message
			var alertMsg = "Please fill in the following fields.:\n";
			var warning1 = document.getElementById('alert1');
			var warning2 = document.getElementById('alert2');

			warning1.style.visibility = 'hidden';
			warning2.style.visibility = 'hidden';


			var l_Msg = alertMsg.length;
	
			for (var i = 0; i < fieldRequired.length; i++){
				var obj = formobj.elements[fieldRequired[i]];
				if (obj){
					if (obj.type == null){
						var blnchecked = false;
						for (var j = 0; j < obj.length; j++){
							if (obj[j].checked){
								blnchecked = true;
							}
						}
						if (!blnchecked){
							alertMsg += " - " + fieldDescription[i] + "\n";
						}
						continue;
					}
		
					switch(obj.type){
						case "checkbox": 
					    if(obj.checked == false) { 
					        alertMsg += " - " + fieldDescription[i] + "\n"; 
					    } 
					    break;
						case "select-one":
							if (obj.selectedIndex == -1 || obj.options[obj.selectedIndex].text == ""){
								alertMsg += " - " + fieldDescription[i] + "\n";
							}
							break;
						case "select-multiple":
							if (obj.selectedIndex == -1){
								alertMsg += " - " + fieldDescription[i] + "\n";
							}
							break;
						case "text":
						case "textarea":
							if (obj.value == "" || obj.value == null){
								alertMsg += " - " + fieldDescription[i] + "\n";
							}
							break;
						default:
					}
				}
			}
		
			if (alertMsg.length != l_Msg){
				warning1.style.visibility = 'visible';
				window.scrollTo(0,findPosY(warning1));
				//alert(alertMsg);
				//return false;
			} else {
				warning1.style.visibility = 'hidden';
				checkAll = true;
			}
			
			var checkOne = false;
			var onefieldRequired = Array("order", "ammountnl", "ammounten", "info", "call", "remark");
			for (var j = 0; j < onefieldRequired.length; j++){
				var obj = formobj.elements[onefieldRequired[j]];
				if (obj){
					 switch(obj.type){
						case "checkbox": 
					    if(obj.checked != false) { 
					        checkOne = true;
					    } 
					    break;
						case "select-one":
							if (obj.selectedIndex != -1 && obj.options[obj.selectedIndex].text != ""){
								checkOne = true;
							}
							break;
						case "select-multiple":
							if (obj.selectedIndex != -1){
								checkOne = true;
							}
							break;
						case "text":
						case "textarea":
							if (obj.value != "" && obj.value != null){
								checkOne = true;
							}
							break;
						default:
					}
				}
			}
			
			if(formobj.elements["order"].checked || formobj.elements["info"].checked || formobj.elements["call"].checked) {
			} else if(document.getElementById('remark').value == "") {
				warning2.style.visibility = 'visible';
				return false;
			}
			
			if (checkOne && checkAll) {
				if (formobj.elements["order"].checked != false && 
						(formobj.elements["ammountnl"].value == "" || !isNumeric(formobj.elements["ammountnl"])) && (formobj.elements["ammounten"].value == "" || !isNumeric(formobj.elements["ammounten"]))
				) {
					warning2.innerHTML = "Vul aub een aantal in.";
					warning2.style.visibility = 'visible';
					return false;
				} else {
					warning2.style.visibility = 'hidden';
					return true;
				}
			} else {
				warning2.style.visibility = 'visible';
				return false;
			}
		}
		
		function isNumeric(x)
		{
			if (!(/^\d+$/.test(x.value)))
			{
				return false;
			}
			return true;
		}