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/*
arch' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/guix/log/?id=f36ed4ddc286bc1105aff63c697e6fbb7310d3df'>root</a>/<a href='/guix/log/gnu?id=f36ed4ddc286bc1105aff63c697e6fbb7310d3df'>gnu</a>/<a href='/guix/log/gnu/system?id=f36ed4ddc286bc1105aff63c697e6fbb7310d3df'>system</a>/<a href='/guix/log/gnu/system/mapped-devices.scm?id=f36ed4ddc286bc1105aff63c697e6fbb7310d3df'>mapped-devices.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/gnu/system/mapped-devices.scm?id=f36ed4ddc286bc1105aff63c697e6fbb7310d3df&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th></tr>
<tr><td><span title='2024-05-27 19:30:22 +0200'>2024-05-27</span></td><td><a href='/guix/commit/gnu/system/mapped-devices.scm?id=ed5bf620ea6366d8468e5b7dad9874c6e0e8c661'>mapped-devices: lvm: Add missing module import.</a><span class='msg-avail'>...</span></td><td>Lars-Dominik Braun</td></tr>
<tr><td><span title='2024-04-08 00:17:57 +0200'>2024-04-08</span></td><td><a href='/guix/commit/gnu/system/mapped-devices.scm?id=49f82fca4130ffcfb16aa0cf89750ab56fb99ad7'>mapped-devices: luks: Specify modules needed at the top-level.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>
<tr><td><span title='2024-04-08 00:13:25 +0200'>2024-04-08</span></td><td><a href='/guix/commit/gnu/system/mapped-devices.scm?id=6062339156ecc42cac59af0d34e22fcc7da3aa4a'>mapped-devices: &lt;mapped-device-type&gt; can specify modules to import.</a><span class='msg-avail'>...</span></td><td>Ludovic Courtès</td></tr>