Based on https://anonscm.debian.org/viewvc/pkg-java/trunk/libxerces2-java/debian/patches/03_bootclasspath.patch?revision=14509, adopted for guix

--- xerces-2_11_0/build.xml.orig	2010-11-26 21:42:11.000000000 +0100
+++ xerces-2_11_0/build.xml	2017-03-28 14:04:41.946606996 +0200
@@ -290,13 +290,14 @@
            destdir="${build.dest}"
            source="${javac.source}"
            target="${javac.target}"
-           classpath="${build.dir}/classes:${tools.dir}/${jar.apis}:${tools.dir}/${jar.resolver}:${tools.dir}/${jar.serializer}"
+           classpath="${build.dir}/classes:${jar.jaxp}:${jar.apis-ext}:${jar.resolver}"
            debug="${debug}" nowarn="true"
            debuglevel="${debuglevel}"
            deprecation="${deprecation}"
            optimize="${optimize}"
            includeAntRuntime="false"
-           includeJavaRuntime="false"
+           includeJavaRuntime="true"
+           bootclasspath="${jar.jaxp}:${jar.apis-ext}:${jar.resolver}"
            excludes="org/xml/sax/** 
                 javax/xml/**
                 org/w3c/dom/*
@@ -1451,13 +1452,14 @@
                destdir="${build.dest}"
                source="${javac.source}"
                target="${javac.target}"
-               classpath="${build.dir}/classes:${tools.dir}/${jar.apis}:${tools.dir}/${jar.resolver}:${tools.dir}/${jar.serializer}"
+               classpath="${build.dir}/classes:${jar.jaxp}:${jar.apis-ext}:${jar.resolver}"
                debug="${debug}"
                debuglevel="${debuglevel}"
                deprecation="${deprecation}"
                optimize="${optimize}"
                includeAntRuntime="false"
-               includeJavaRuntime="false"
+               includeJavaRuntime="true"
+               bootclasspath="${jar.jaxp}:${jar.apis-ext}:${jar.resolver}"
                excludes="org/xml/sax/** 
                     javax/xml/**
                     org/w3c/dom/*

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<div class='path'>path: <a href='/guix/log/?id=dafcf2fcc015e66a7924597193f0f012dad1d0d6'>root</a>/<a href='/guix/log/build-aux?id=dafcf2fcc015e66a7924597193f0f012dad1d0d6'>build-aux</a>/<a href='/guix/log/build-aux/build-self.scm?id=dafcf2fcc015e66a7924597193f0f012dad1d0d6'>build-self.scm</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/guix/log/build-aux/build-self.scm?id=dafcf2fcc015e66a7924597193f0f012dad1d0d6&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2020-08-24 13:35:24 +0200'>2020-08-24</span></td><td><a href='/guix/commit/build-aux/build-self.scm?id=4c0c65acfade63ce0549115d19db4b639c1e9992'>Use "guile-zlib" and "guile-lzlib" instead of (guix config).</a><span class='msg-avail'>...<span class='msg-tooltip'>* Makefile.am (MODULES): Remove guix/zlib.scm and guix/lzlib.scm,
(SCM_TESTS): remove tests/zlib.scm, tests/lzlib.scm.
* build-aux/build-self.scm (make-config.scm): Remove unused %libz variable.
* configure.ac: Remove LIBZ and LIBLZ variables and check instead for
Guile-zlib and Guile-lzlib.
* doc/guix.texi ("Requirements"): Remove zlib requirement and add Guile-zlib
and Guile-lzlib instead.
* gnu/packages/package-management.scm (guix)[native-inputs]: Add "guile-zlib"
and "guile-lzlib",
[inputs]: remove "zlib" and "lzlib",
[propagated-inputs]: ditto,
[arguments]: add "guile-zlib" and "guile-lzlib" to Guile load path.
* guix/config.scm.in (%libz, %liblz): Remove them.
* guix/lzlib.scm: Remove it.
* guix/man-db.scm: Use (zlib) instead of (guix zlib).
* guix/profiles.scm (manual-database): Do not stub (guix config) in imported
modules list, instead add "guile-zlib" to the extension list.
* guix/scripts/publish.scm: Use (zlib) instead of (guix zlib) and (lzlib)
instead of (guix lzlib),
(string-&gt;compression-type, effective-compression): do not check for zlib and
lzlib availability.
* guix/scripts/substitute.scm (%compression-methods): Do not check for lzlib
availability.
* guix/self.scm (specification-&gt;package): Add "guile-zlib" and "guile-lzlib"
and remove "zlib" and "lzlib",
(compiled-guix): remove "zlib" and "lzlib" arguments and add guile-zlib and
guile-lzlib to the dependencies, also do not pass "zlib" and "lzlib" to
"make-config.scm" procedure,
(make-config.scm): remove "zlib" and "lzlib" arguments as well as %libz and
%liblz variables.
* guix/utils.scm (lzip-port): Use (lzlib) instead of (guix lzlib) and do not
check for lzlib availability.
* guix/zlib.scm: Remove it.
* m4/guix.m4 (GUIX_LIBZ_LIBDIR, GUIX_LIBLZ_FILE_NAME): Remove them.
* tests/lzlib.scm: Use (zlib) instead of (guix zlib) and (lzlib)
instead of (guix lzlib), and do not check for zlib and lzlib availability.
* tests/publish.scm: Ditto.
* tests/substitute.scm: Do not check for lzlib availability.
* tests/utils.scm: Ditto.
* tests/zlib.scm: Remove it.
</span></span></td><td>Mathieu Othacehe</td></tr>