How to get namespaces in the root QDomElement?

[kkkiio]

most xml like to declare namespaces in the root element like this:

<root xmlns="a" xmlns:x="b">
    <x:e />
</root>

but call QDomDocument::setContent with setting namespaceProcessing to true will result unexpected behavior:

rootElem.prefix(); // ""
rootElem.namespaceURI(); // "a"
eElem.prefix(); // "x"
eElem.namespaceURI(); // "b"
rootElem.attributes(); // empty map!!!  can't even parse manually

Is there an easy way to get all namespaces in a QDomElement?

thanks.