diff --git a/.cvsignore b/.cvsignore
index e47b601..96f1235 100644
--- a/.cvsignore
+++ b/.cvsignore
@@ -2,4 +2,5 @@ bin
 jskad.log
 savant.log
 qd.log
+TEST*
 *~
diff --git a/build.xml b/build.xml
index cfad9ca..909bdcc 100644
--- a/build.xml
+++ b/build.xml
@@ -25,7 +25,9 @@
      extensions/jmf.jar
 
      See the developers site, linked to from http://thdltools.sf.net/,
-     for info on where to find these.
+     for info on where to find these.  (You may be able to use Ant's
+     copies of some of them, if you really can't wait to get started.
+     Examine the contents of '$ANT_HOME/lib'.)
 
 -->
 
@@ -47,6 +49,7 @@
   <property name="license" location="license"/>
   <property name="bin" location="bin"/>
   <property name="jskadbin" location="bin/jskad"/>
+  <property name="junitbin" location="bin/for-junit"/>
   <property name="qdbin" location="bin/qd"/>
   <property name="ttstandalonebin" location="bin/tt-standalone"/>
   <property name="ttappletjwsbin" location="bin/tt-applet-and-java-web-start"/>
@@ -156,6 +159,7 @@
     <mkdir dir="${dist}/source"/>
     <mkdir dir="${bin}"/>
     <mkdir dir="${jskadbin}"/>
+    <mkdir dir="${junitbin}"/>
     <mkdir dir="${qdbin}"/>
     <mkdir dir="${ttstandalonebin}"/>
     <mkdir dir="${tthandheldbin}"/>
@@ -167,8 +171,30 @@
   </target>
 
 
-  <target name="test-all"
-          depends="clean,distclean,compile,dist,src-dist,self-contained-dist,public-javadocs-dist,private-javadocs-dist,releases,web-start-releases,nightly-build"
+  <!--
+       See http://thdltools.sourceforge.net/BuildSystems.html for full
+       details on unit testing our software.  If you're eager enough
+       to get started, just read
+       extensions/to-be-installed-with-ant/README.TXT.
+
+       Just as with 'ant dist', it is wise to 'ant clean' before
+       running 'ant check'.
+  -->
+  <target name="check"
+          description="Compiles and runs all JUnit tests (that can be run given the present extension JARs) for the entire project.  Our coverage is currently quite low."
+          depends="compile-junit-tests">
+    <ant antfile="junitbuild.xml" target="run-all-junit-tests"
+         inheritAll="false" inheritRefs="false">
+       <reference refid="entire.class.path"/>
+       <property name="junitbin" value="${junitbin}"/>
+    </ant>
+    <echo message=""/>
+    <echo message="You may now examine the files TEST-* for more details."/>
+  </target>
+
+  <!-- Use 'ant check' for testing the software, and this merely for putting the build system through its paces: -->
+  <target name="test-all-ant-targets"
+          depends="clean,distclean,compile,dist,src-dist,self-contained-dist,public-javadocs-dist,private-javadocs-dist,releases,web-start-releases,check,nightly-build"
           description="runs every target in this buildfile in a smart order; useful for testing the buildfile and your build environment" />
 
 
@@ -255,6 +281,20 @@
     </copy>
   </target>
 
+  <target name="compile-junit-tests" depends="init"
+          description="compiles all JUnit test cases that can be compiled in the present CLASSPATH (NB that this distinction is just wishful thinking for now becuase we have such weak test coverage at this point)" >
+    <antcall target="our-internal-javac-task">
+      <param name="mybin" value="${junitbin}"/>
+      <param name="my.included.source.file"
+             value="org/thdl/util/ThdlLazyExceptionTest.java"/>
+    </antcall>
+    <antcall target="our-internal-javac-task">
+      <param name="mybin" value="${junitbin}"/>
+      <param name="my.included.source.file"
+             value="org/thdl/util/TrieTest.java"/>
+    </antcall>
+  </target>
+
   <target name="savant-compile" depends="init"
           description="compiles Savant" >
     <antcall target="copy-tmw-fonts-to-bin-dir">
@@ -529,7 +569,7 @@
                   includes="*"
                   prefix="."/>
       <zipfileset dir="."
-                  includes="build.xml"
+                  includes="*build.xml"
                   prefix="."/>
       <zipfileset dir="."
                   includes="docs/*package-list/**"
@@ -636,7 +676,7 @@
 
 
 
-<!-- DLC FIXME: This used to inlude Jskad2Javascript.class, etc.  But it no longer does.  Compile those extra files, if Edward hasn't removed them! -->
+<!-- DLC FIXME: This used to include Jskad2Javascript.class, etc.  But it no longer does.  Compile those extra files if Edward hasn't removed them! -->
   <target name="jskad-all-in-one-dist" depends="jskad-compile"
           description="generates the self-contained binary distribution for Jskad" >
     <!-- Now put everything in ${bin} and ${ext}/netscape, plus
@@ -706,6 +746,9 @@
     <delete file="${dist}/QuillDriver.jnlp"/>
     <delete file="${dist}/Jskad.jnlp"/>
     <delete file="${source}/org/thdl/util/ThdlVersion.java"/>
+    <delete>
+      <fileset dir="." includes="TEST-org.thdl*"/>
+    </delete>
   </target>
 
 
@@ -801,7 +844,7 @@
     </java>
   </target>
 
-<!-- DLC NOW -->
+<!-- DLC NOW convert to junit tests. -->
   <target name="test-tsheg-bar" depends="jskad-dist" description="runs tsheg bar tests">
     <java classname="org.thdl.tib.text.tshegbar.test" fork="yes">
       <classpath>
@@ -960,10 +1003,6 @@
       <src path="${source}"/>
       <include name="${my.included.source.file}" />
 
-      <!-- Exclude JUnit tests: -->
-      <exclude name="**/*Test.java" />
-      <exclude name="**/*AllTests.java" />
-
       <!-- Don't compile these resources (we could leave this out, but
            Ant's debugging output would confuse us, and having this
            explicit is a Good Thing: -->
@@ -1278,7 +1317,11 @@ public class ThdlVersion {
 ]]></echo>
   </target>
 
-<!-- DLC TODO: jardiffs for the JWS stuff. -->
+  <!--
+       Note that jardiffs for the JWS stuff are done by the JWS system
+       itself when appropriate and when the server is configured
+       correctly.  We have no work to do on that front.
+  -->
   <target name="copy-SQD-jars"
           description="Unpacks the JARs/WARs/ZIP files that Savant and QuillDriver use to the chosen bin/ directory">
     <unjar src="${ext}/jdom.jar" dest="${unjardest}"/>
@@ -1297,6 +1340,7 @@ public class ThdlVersion {
       <fileset dir="Fonts/TibetanMachineWeb"/>
     </copy>
   </target>
+
 </project>
 
 <!-- My TO-DO list: -->
diff --git a/extensions/README.TXT b/extensions/README.TXT
new file mode 100644
index 0000000..7dc8672
--- /dev/null
+++ b/extensions/README.TXT
@@ -0,0 +1,5 @@
+This directory is where we place third-party JARs of which our
+software is a client.  The subdirectory to-be-installed-with-ant/
+contains a README file for you, also.
+
+See 'http://thdltools.sf.net/BuildSystems.html' for more info.
diff --git a/extensions/to-be-installed-with-ant/README.TXT b/extensions/to-be-installed-with-ant/README.TXT
new file mode 100644
index 0000000..8492b11
--- /dev/null
+++ b/extensions/to-be-installed-with-ant/README.TXT
@@ -0,0 +1,8 @@
+Copy the JARs in this directory into Ant's lib/ directory (i.e.,
+$ANT_HOME/lib, the same directory where 'optional.jar', shipped with
+Ant, lives).  The build system has been designed so that you needn't
+do this to do basic development activities, but some build targets are
+only functional if you perform this step.
+
+See http://thdltools.sf.net/BuildSystems.html for more info.
+
diff --git a/extensions/to-be-installed-with-ant/junit.jar b/extensions/to-be-installed-with-ant/junit.jar
new file mode 100644
index 0000000..674d71e
Binary files /dev/null and b/extensions/to-be-installed-with-ant/junit.jar differ
diff --git a/junitbuild.xml b/junitbuild.xml
new file mode 100644
index 0000000..44911e5
--- /dev/null
+++ b/junitbuild.xml
@@ -0,0 +1,44 @@
+<!-- @author David Chandler, dchandler@users.sourceforge.net
+
+     We have a document,
+     http://thdltools.sourceforge.net/BuildSystems.html, that you
+     probably should read.
+-->
+
+<project name="THDLTools" default="fail-nicely" basedir=".">
+
+  <description>
+    This Jakarta Ant buildfile is used to do the low-level work of
+    unit testing our system.  This is separate from build.xml because
+    to use this build file, you must have installed JUnit and the
+    JUnit Ant tasks (i.e., $ANT_HOME/lib/junit.jar and
+    $ANT_HOME/lib/optional.jar).  Thus, this buildfile contains only
+    targets that must interact with JUnit.
+
+    Read the comments of this buildfile to learn more, or see
+    'http://thdltools.sourceforge.net/BuildSystems.html'.
+  </description>
+
+  <taskdef name="junit"
+           classname="org.apache.tools.ant.taskdefs.optional.junit.JUnitTask"/>
+
+  <target name="fail-nicely"
+          description="Tells the user to use build.xml, not this subbuildfile.">
+    <fail message="Do not use this file directly; use build.xml file instead, which then uses this file."/>
+  </target>
+
+
+  <!-- This creates output files TEST* in the Jskad/ directory. -->
+  <target name="run-all-junit-tests"
+          description="Assuming that compilation of appropriate classes has been done, this target runs all the JUnit tests in the project.">
+    <junit fork="no" printsummary="yes" haltonfailure="yes" haltonerror="yes">
+      <classpath>
+        <pathelement location="${junitbin}"/>
+        <path refid="entire.class.path"/>
+      </classpath>
+      <formatter type="plain"/>
+      <test name="org.thdl.util.ThdlLazyExceptionTest"/>
+      <test name="org.thdl.util.TrieTest"/>
+    </junit>
+  </target>
+</project>
diff --git a/jwsbuild.xml b/jwsbuild.xml
index 63408dd..ac206b2 100644
--- a/jwsbuild.xml
+++ b/jwsbuild.xml
@@ -2,9 +2,7 @@
 
      We have a document,
      http://thdltools.sourceforge.net/BuildSystems.html, that you
-     probably should read.  FIXME: update this document to describe
-     the two-buildfile system.
-
+     probably should read.
 -->
 
 <project name="THDLTools" default="fail-nicely" basedir=".">
@@ -16,7 +14,7 @@
     This is separate from build.xml because to use this build file,
     you must have installed the Venus Application Publisher's (Vamp's)
     Ant tasks.  Read the comments of this buildfile to learn more, or
-    see http://thdltools.sourceforge.net/BuildSystems.html.
+    see 'http://thdltools.sourceforge.net/BuildSystems.html'.
   </description>