> I have a new one: I have to find the "root"-node of a node
> (not the document root, but a certain root).

you don't say what you mean by this so its hard to give explict code or advice.

> A list of nodes 1,2,3 is acceptable, too.

that's more or less what your posted code does

//page[@id='4']/ancestor:node()"

is the sequence (or set in XSLT 1) of 4 nodes
<pages> <page id="1">  <page id="2"> <page id="4">
in what way is this not what you need?

Perhaps you just want the id of the outermost page ancestor of the
current node which is

<xsl:value-of select="ancestor::page[last()]/@id"/>

but that's just a guess.

David

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