XSLT pass through

Hi,

Assuming a XML document like this:

<myRoot xmlns:targetNS="http://myNS.com">
<hello><targetNS:goodbye>123</targetNS:goodbye></hello>
</myRoot>

How would I get an XSLT result that reproduces all tags that are not of
namespace "targetNS" exactly as it was input? I only want to manipulate
the elements that are of namespace "targetNS", all the rest are to be
reproduced as-is.

Thank you!
Wong