//Client:

window.onerror = function(msg, url, line, col, error) {
   Client.sendEvent('error', {msg: msg, url: url, line: line, col: col, error: error});
   return true;
};

//Server:

this.onEventReceived = function(user, key, data)
    {
        if(key == 'error') {
            KnuddelsServer.getDefaultLogger().error("Client-Error from " + user.getNick() + ": " + JSON.stringify(data));
        }
    };