     onUpdateFailed: (event, error)-> 
     onUpdateCompleted: (manifest) -> return true
     onModuleBeginDownload: (module) -> 
-    onModuleDownloadFailed: (event, module) -> 
+    onModuleDownloadFailed: (event, module, error) -> 
     onModuleDownloadProgress: (event, module) -> 
     onTotalDownloadProgress: (progress) -> 
     onModuleDownloaded: (module) -> 

            return unless key? # wierd error
            return unless key.indexOf(@prefix) is 0
            return if key in useful
            @del_content(key)
            return
        return

                return
            @set_content @make_key(module), module_source, (err, content) =>
                if err?
                    @emit("ModuleDownloadFailed", null, module, new DBError(module.url, err))
                    return
                module.source = module_source
                module.loaded = module.size
