AJS Framework: gadget user preference template 'FilterPicker' is unusable due to bug

I am developing a gadget through the plugin SDK v4.1.6 and want to use the FilterPicker user preference template (http://wiki.customware.net/repository/display/ATLASSIAN/Making+Your+Gadget+Configurable). I get an error when trying to diplay the gadget configuration (see attachement)

Cause: the jira.widget object does not have an autocomplete object.

I call the filter picker in my gadget descriptor javascript-code:
...
AJS.gadget.fields.filterPicker(gadget, "filter"),
...

error stacktrace: Uncaught TypeError: Cannot read property 'REST' of undefined gadget-common-fields.js:592
AJS.gadget.fields.autocomplete.Filters gadget-common-fields.js:592
callback gadget-common-fields.js:56
AJS.gadgets.templater.Custom.AJS.$.extend.callback ajs.gadgets.templater.form.js:26
jQuery.extend.each jquery.js:658
jQuery.fn.jQuery.each jquery.js:271
AJS.gadgets.templater.Custom.AJS.$.extend.callback ajs.gadgets.templater.form.js:22
build.AJS.$.ajax.url ajs.gadgets.templater.base.js:262
jQuery.extend.each jquery.js:658
jQuery.fn.jQuery.each jquery.js:271
build ajs.gadgets.templater.base.js:261
(anonymous function) ajs.gadgets.templater.base.js:162
getDescriptorData.AJS.$.each.reqOptions.success ajs.gadgets.templater.base.js:167
jQuery.extend.success ajax.js:72
AG.ajax.handleCallbacks makeRequestToJQueryAjaxCallbackTransformer.js:34
AG.ajax.jQuery.params.success jQuery.js:31
jQuery.Callbacks.fire jquery.js:1046
jQuery.Callbacks.self.fireWith jquery.js:1164
done jquery.js:7399
jQuery.ajaxTransport.send.callback jquery.js:8180