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diff --git a/tex/context/base/core-rul.mkii b/tex/context/base/core-rul.mkii
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+%D \module
+%D   [       file=core-rul,
+%D        version=1998.10.16,
+%D          title=\CONTEXT\ Core Macros,
+%D       subtitle=Ruled Stuff Handling,
+%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.
+
+\unprotect
+
+% The next implementation is frozen! It preserves the depth,
+% otherwise we get problems with framed display math and auto
+% width.
+
+\def\shapeboxstrut % put this in front if needed !
+  {\vrule\!!width\zeropoint\!!height\ht\shapebox\!!depth\dp\shapebox}
+
+\let\framedboxwidth \!!zeropoint
+\let\framedboxheight\!!zeropoint
+\let\framedboxdepth \!!zeropoint
+
+\def\doreshapeframedbox % frozen, that is ... \shapeboxstrut added
+  {\beginofshapebox
+   \unvcopy\framebox
+   \endofshapebox
+   \global\@@globalwidth\zeropoint
+   \edef\framedboxwidth {\the\wd\framebox}%
+   \edef\framedboxheight{\the\ht\framebox}%
+   \edef\framedboxdepth {\the\dp\framebox}%
+   \resetshapeframebox
+   \reshapebox
+     {\setbox0\hbox
+        {\strut\ifhbox\shapebox\shapeboxstrut\unhbox\else\box\fi\shapebox}%
+      \global\advance\framednoflines \plusone
+      \ifdim\framedlastlength>\zeropoint\else
+        \global\framedlastlength\wd0
+      \fi
+      \ifdim\wd0>\@@globalwidth
+        \global\@@globalwidth\wd0
+      \fi}%
+   \ifreshapingfailed
+      % no need for anothr pass or finalizer
+   \else
+      \dosetraggedcommand\localformat
+      \raggedcommand
+      \ifboxhasheight
+        \setbox\framebox\vbox to \localheight
+          {\hsize\@@globalwidth
+           \reshapebox{\hbox to \hsize{\ifhbox\shapebox\shapeboxstrut\unhbox\else\box\fi\shapebox}}%
+           \dobeforeframedbox
+           \innerflushshapebox
+           \doafterframedbox}%
+      \else
+        \setbox\framebox\vbox to \framedboxheight % \ht\framebox
+          {\hsize\@@globalwidth
+           \reshapebox{\hbox to \hsize{\ifhbox\shapebox\shapeboxstrut\unhbox\else\box\fi\shapebox}}%
+           \ifcase\reshapeframeboxmethod
+             \or \innerflushshapebox \or \innerflushshapebox
+           \fi}%
+        \ifcase\reshapeframeboxmethod \or
+          \dp\framebox\framedboxdepth % \strutdp otherwise problem with math
+        \fi
+      \fi
+      \ifdim\framedlastlength=\zeropoint\global\framedlastlength\wd\framebox\fi
+      \ifcase\framednoflines\global\framednoflines\plusone\fi
+   \fi}
+
+\protect \endinput