I just downloaded last version (2.2) to use it and I made a few changes to
optimize the shrinked size : 
function cleanup and onDomLoad are only called by themselves, so you don't
need to name them : 
/*onDomLoad = */ function(){...

You used OBJECT = "object" constant but not everywhere (one place is missing)

Many var could be combined to reduce the weight
var b = doc.getElementsByTagName("body")[0];
var o = createElement(OBJECT);
becomes :
var b = doc.getElementsByTagName("body")[0]
,o = createElement(OBJECT);


Bye,

Thomas.