function insertAtCaret(doc, areaId, text) {
    var txtarea = doc.getElementById(areaId);
    var scrollPos = txtarea.scrollTop;
    var strPos = 0;
    var br = ((txtarea.selectionStart || txtarea.selectionStart == '0') ? "ff" : (doc.selection ? "ie" : false ) );
    if (br == "ie") {
        txtarea.focus();
        var range = doc.selection.createRange();
        range.moveStart('character', -txtarea.value.length);
        strPos = range.text.length;
    } else if (br == "ff") strPos = txtarea.selectionStart;
    var front = (txtarea.value).substring(0, strPos);
    var back = (txtarea.value).substring(strPos, txtarea.value.length);
    txtarea.value = front + text + back;
    strPos = strPos + text.length;
    if (br == "ie") {
        txtarea.focus();
        var range = doc.selection.createRange();
        range.moveStart('character', -txtarea.value.length);
        range.moveStart('character', strPos);
        range.moveEnd('character', 0);
        range.select();
    } else if (br == "ff") {
        txtarea.selectionStart = strPos;
        txtarea.selectionEnd = strPos;
        txtarea.focus();
    }
    txtarea.scrollTop = scrollPos;
}