function isValidNumber(form, field, errorMsg)
{
	var formObj = document.forms[form];
	if (!formObj)
	{
	    alert("Error: Could not get Form <"+form+">");
	    return false;
	}
	var fieldObj = document.forms[form].elements[field];
	if (!fieldObj)
	{
	    alert("Error: Could not get Field <"+form+":"+field+">");
	    return false;
	}

	if ((fieldObj.value.length == 0) || (fieldObj.value.search('[^0-9]') != -1))
	{
	    alert(errorMsg);
	    fieldObj.select();
	    return false;
	}
	else
	{
	    return true;
	}
}
function isValidNumberMax(form, field, max, errorMsg)
{
	var formObj = document.forms[form];
	if (!formObj)
	{
	    alert("Error: Could not get Form <"+form+">");
	    return false;
	}
	var fieldObj = document.forms[form].elements[field];
	if (!fieldObj)
	{
	    alert("Error: Could not get Field <"+form+":"+field+">");
	    return false;
	}

	if (isNaN(fieldObj.value))
	{
	    alert("Error: Attempting to check max value of a non-number: "+fieldObj.value);
	}

	if (eval(fieldObj.value) > max)
	{
	    alert(errorMsg);
	    fieldObj.select();
	    return false;
	}
	else
	{
	    return true;
	}
}
function isValidNumberMin(form, field, min, errorMsg)
{
	var formObj = document.forms[form];
	if (!formObj)
	{
	    alert("Error: Could not get Form <"+form+">");
	    return false;
	}
	var fieldObj = document.forms[form].elements[field];
	if (!fieldObj)
	{
	    alert("Error: Could not get Field <"+form+":"+field+">");
	    return false;
	}

	if (isNaN(fieldObj.value))
	{
	    alert("Error: Attempting to check min value of a non-number: "+fieldObj.value);
	}

	if (eval(fieldObj.value) < min)
	{
	    alert(errorMsg);
	    fieldObj.value = min;
	    fieldObj.select();
	    return false;
	}
	else
	{
	    return true;
	}
}