JavaScript error on AccordionPanel

When i load a page with AccordionPanel i get these errors:

Error:

{expandedBg:"#63699c", hoverBg:"#63699c", collapsedBg:"#6b79a5", expandedTextColor:"#ffffff", expandedFontWeight:"bold", hoverTextColor:"#ffffff", collapsedTextColor:"#ced7ef", collapsedFontWeight:"normal", hoverTextColor:"#ffffff", borderColor:"#1f669b", panelHeight:200, onHideTab:null, onShowTab:null}

.extend is not a function
source file: http://localhost:8080/myfaces-example-sandbox/faces/myFacesExtensionResource/org.apache.myfaces.renderkit.html.util.MyFacesResourceLoader/11449359/accordion.HtmlAccordionPanelRenderer/customRico.js
Line: 50

Error:

{expandedBg:"#63699c", hoverBg:"#63699c", collapsedBg:"#6b79a5", expandedTextColor:"#ffffff", expandedFontWeight:"bold", hoverTextColor:"#ffffff", collapsedTextColor:"#ced7ef", collapsedFontWeight:"normal", hoverTextColor:"#ffffff", borderColor:"#1f669b", panelHeight:200, closedPanelHeight:50, useRealHeight:true, onHideTab:null, onShowTab:null}

.extend is not a function
source file: http://localhost:8080/myfaces-example-sandbox/faces/myFacesExtensionResource/org.apache.myfaces.renderkit.html.util.MyFacesResourceLoader/11449359/accordion.HtmlAccordionPanelRenderer/customRico.js
Line: 276