/////////////// API Functions to manipulate forms on the page //////////////

// Check a checkbox on a form
//    Returns false if element does not exist, or is disabled
function FormCheck(strFormName, strInputName, strInputValue)
{
    var strXPath = "";

    // Form name is optional, include it if necessary
    if (strFormName)
        strXPath += '//form[@name=\'' + strFormName + '\']';

    // Input name is mandatory (else we cannot find the input box...)
    strXPath += '//input[@name=\'' + strInputName + '\'';

    // Input value is also optional
    if (strInputValue)
	strXPath += ' and @value=\'' + strInputValue + '\'';
    strXPath += ']';

    var elem = document.evaluate(strXPath, document, null, XPathResult.ANY_UNORDERED_NODE_TYPE, null).singleNodeValue;

    // Return without action if element does not exist or is disabled
    if (!elem || elem.disabled)
        return false;

    // Otherwise check the box and return true
    elem.checked = "checked";
    return true;
}