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diff --git a/tex/context/base/xtag-exp.tex b/tex/context/base/xtag-exp.tex
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+%D \module
+%D   [       file=xtag-exp,
+%D        version=2001.08.20,
+%D          title=\CONTEXT\ XML Macros,
+%D       subtitle=Expansion,
+%D         author=Hans Hagen,
+%D           date=\currentdate,
+%D      copyright={PRAGMA / Hans Hagen \& Ton Otten}]
+%C
+%C This module is part of the \CONTEXT\ macro||package and is
+%C therefore copyrighted by \PRAGMA. See mreadme.pdf for
+%C details.
+
+\writestatus{loading}{ConTeXt XML Macros / Expansion}
+
+\unprotect
+
+%D Files
+
+\newcounter\XMLfilenesting \let\restoreXMLelements\relax
+
+\def\startXMLreading
+  {\increment \XMLfilenesting \relax
+   \ifcase\XMLfilenesting\or
+     \ifprocessingXML
+       \let\restoreXMLelements\relax
+     \else
+       \let\restoreXMLelements\disableXMLelements
+       \enableXMLelements
+     \fi
+   \fi}
+
+\def\stopXMLreading
+  {\ifcase\XMLfilenesting\or
+     \restoreXMLelements
+     \let\restoreXMLelements\relax
+   \fi
+   \decrement \XMLfilenesting \relax}
+
+\ifnum\texengine=\luatexengine
+    \def\enableXMLfiledata
+      {\prependtoks \enableXMLelements      \to \mainoutput % brrr, will change
+       \appendtoks  \forcefileexpansiontrue \to \everyenableXML
+       \let\enableXMLfiledata\relax}
+\else
+    \def\enableXMLfiledata
+      {\prependtoks \enableXMLelements      \to \mainoutput % brrr, will change
+       \appendtoks  \startXMLreading        \to \everybeforeutilityread
+       \appendtoks  \stopXMLreading         \to \everyafterutilityread
+       \appendtoks  \forcefileexpansiontrue \to \everyenableXML
+       \let\enableXMLfiledata\relax}
+\fi
+
+\setupXMLprocessing[\c!state=\v!start]
+
+\appendtoks
+  \ifproductionrun \enableXMLfiledata \fi
+\to \aftersetupXMLprocessing
+
+%D Here we overload the mark handler.
+
+\ifnum\texengine=\luatexengine \else
+
+    \def\XMLexpanded#1%
+      {\bgroup
+       \honorunexpanded
+       \dontexpandencoding
+       \xdef\@@globalexpanded{\noexpand#1}% why \noexpand?
+       \egroup
+       \@@globalexpanded}
+
+    \let\normalsetnormalmark\setnormalmark
+
+    \long\def\setnormalmark#1% overloaded
+      {\ifprocessingXML
+         \expandafter\setXMLexpandedmark
+       \else
+         \expandafter\normalsetnormalmark
+       \fi#1}
+
+    \def\setXMLexpandedmark#1#2% using a tok prevents unwanted expansion in mark
+      {\XMLexpanded{\scratchtoks{\enableXMLelements#2}}%
+       \setxvalue{\@@crk\string#1}{\the\scratchtoks}%
+       \normalmarks#1{\the\scratchtoks}}
+
+\fi
+
+\protect \endinput