xsltEvalOneUserParam() is not working, without playing with member values of internal structure - xsltTransformContext.

Example code:

xctxt = xsltNewTransformContext(stylesheet, doc);
xsltEvalOneUserParam(xctxt, name, value);

In this xsltEvalOneUserParam() will always return null for all XPATH expressions specified in variable value. Reason for this seem to be unset initialContextDoc and initialContextNode members of xsltTransformContext structure.

If code modified like this:

xctxt = xsltNewTransformContext(stylesheet, doc);
// stolen from xsltApplyStylesheetInternal()
xctxt->initialContextDoc = doc;
xctxt->initialContextNode = (xmlNodePtr) doc;
xsltEvalOneUserParam(xctxt, name, value);

everything works ok. But, this unfortunately touches members of structure that is not part of API (http://xmlsoft.org/XSLT/html/libxslt-xsltInternals.html), and therefore is possibly non-portable.
Reason why xsltEvalOneUserParam() works correctly in xsltApplyStylesheet*() is that, this function sets initialContextDoc/Node members after creating context.

IMHO xsltNewTransformContext() function should set it when creating context...

Thanks