var current_tab_id = 1;

function switchTab(to_id) {
    if(current_tab = document.getElementById("tab_" + current_tab_id)) {
        current_tab.style.display = "none";
    }
    if(new_tab = document.getElementById("tab_" + to_id)) {
        new_tab.style.display = "block";
    }
    if(current_tab_link = document.getElementById("tab_select_" + current_tab_id)) {
        current_tab_link.className = "";
    }
    if(new_tab_link = document.getElementById("tab_select_" + to_id)) {
        new_tab_link.className = "selected";
    }
    current_tab_id = to_id
    return;
}