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// RBL CHECK LINK: <pre><nowiki>

$(function () {
    var addr;
    if (mw.config.get('wgCanonicalNamespace') == "Special" && mw.config.get('wgCanonicalSpecialPageName') == "Contributions")
        addr = document.forms[0].target.value;
    else if (mw.config.get('wgCanonicalNamespace') == "User" || mw.config.get('wgCanonicalNamespace') == "User_talk")
        addr = mw.config.get('wgTitle');

    if (!/^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$/.test(addr)) return;  // not an IP

    mw.util.addPortletLink('p-tb', 'http://www.robtex.com/rbls/'+addr+'.html',
                   'RBL check', 't-rblcheck', 'Multi-RBL check');
});

// </nowiki></pre>