embed xml code into plugin

yeah, just load it as a string

var krpanoxml:String = "<krpano>more krpano code</krpano>";
krpano.call("loadxml("+escape(krpanoxml)+")");

the string should be escaped though. So use escape(krpanoxml).

Edit:
Sorry I missunderstood. You want to load a normal xml intoo a custom plugin, and read the xml, and fire functions accordingly? thats a different subject (and not much to do with krpano). I would normally define the action in the xml

<somexml> <customplugin onclick="trace('test')" /></somexml>

in your plugin, you load the xml and read out the onclick attribute, and then wrap a krpano.call around it. Else you can use this[valuefromxml]() where valuefromxml is the string thats stored in the onclick (xml)