ZK - Open Source Ajax Java Framework

I have created a custom component named "lookupbox" by extending bandbox.
When I use the component in my page as below:

<window id="winLkp" position="center" border="normal" sizable="true"
width="500px" title="lookup field test" height="400px">

<hbox>
<lookupbox width="100px"></lookupbox>

</hbox>

</window>

Visual editor gives error "Unknown Component : lookupbox".
However the above code works during runtime.
Does visual editor supports custom components created within the project?

lang-addon.xml as follows:
<language-addon>
<addon-name>lookupbox</addon-name>
<!-- Specifies what other addon this depends
<depends>zul.inp</depends>
-->

<!-- Which language this addon will be added to -->
<language-name>xul/html</language-name>
<component>
<component-name>lookupbox</component-name>
<extends>bandbox</extends>
<component-class>
com.dss.framework.ui.zk.LookupField
</component-class>
<widget-class>dss.Lookupbox</widget-class>
</component>
</language-addon>
----------------
Added entry in ZK.xml

<language-config>
<addon-uri>/WEB-INF/lang-addon.xml</addon-uri>
</language-config>
-------------

NO, visual editor has not yet supports custom components created within the project.