diff --git a/dev/build.xml b/dev/build.xml
index 9dfd13c..ad28a03 100755
--- a/dev/build.xml
+++ b/dev/build.xml
@@ -289,7 +289,7 @@
              includes="${gwt.junit.testcase.dev.core.includes}"
              excludes="${gwt.junit.testcase.dev.core.excludes}"/>
     <gwt.junit test.name="dev" test.out="${junit.out}"
-               test.args="${test.args}"
+               test.args="${test.args} -devMode"
                test.jvmargs="${test.jvmargs}"
                test.cases="tests.dev.core">
       <extraclasspaths>
diff --git a/elemental/build.xml b/elemental/build.xml
index fe86d31..926a2de 100644
--- a/elemental/build.xml
+++ b/elemental/build.xml
@@ -77,7 +77,7 @@
 
   <target name="test.dev.htmlunit" if="generated" depends="compile.tests"
           description="Run tests with HtmlUnit in dev mode">
-    <run-tests output="${junit.out}/dev" args="${test.args}" classes="**/AllTests.class"/>
+    <run-tests output="${junit.out}/dev" args="${test.args} -devMode" classes="**/AllTests.class"/>
   </target>
 
   <target name="test.web.htmlunit" if="generated" depends="compile.tests"
diff --git a/user/build.xml b/user/build.xml
index 8108af3..2e43d09 100755
--- a/user/build.xml
+++ b/user/build.xml
@@ -45,7 +45,7 @@
     Test args can be specified per test target type.
   -->
   <property name="test.args.dev.selenium"
-            value='${test.args} -out www -runStyle "Selenium:${gwt.hosts.dev.selenium}"'/>
+            value='${test.args} -devMode -out www -runStyle "Selenium:${gwt.hosts.dev.selenium}"'/>
   <property name="test.args.web.selenium"
             value='${test.args} -prod -out www -generateJsInteropExports -runStyle "Selenium:${gwt.hosts.web.selenium}"'/>
   <property name="test.args.web.htmlunit"
@@ -315,7 +315,7 @@
              includes="${gwt.junit.testcase.dev.includes}"
              excludes="${gwt.junit.testcase.dev.excludes}"/>
     <gwt.junit test.name="test.emma.htmlunit"
-               test.args="${test.args} "
+               test.args="${test.args} -devMode"
                test.jvmargs="${test.jvmargs}"
                test.out="${junit.out}/emma-htmlunit"
                test.cases="test.emma.htmlunit.tests">
@@ -334,7 +334,7 @@
              includes="${gwt.junit.testcase.dev.includes}"
              excludes="${gwt.junit.testcase.dev.excludes}"/>
     <gwt.junit test.name="test.dev.htmlunit"
-               test.args="${test.args} "
+               test.args="${test.args} -devMode"
                test.jvmargs="${test.jvmargs}"
                test.out="${junit.out}/dev-htmlunit"
                test.cases="test.dev.htmlunit.tests">
@@ -670,7 +670,7 @@
              includes="${gwt.tck.testcase.dev.includes}"
              excludes="${gwt.tck.testcase.dev.excludes}"/>
     <gwt.junit test.name="test.dev.htmlunit"
-               test.args="${test.args} "
+               test.args="${test.args} -devMode"
                test.jvmargs="-ea -Dcom.google.gwt.sample.validationtck.util.Failing.include=true"
                test.out="${junit.out}/tck-dev-htmlunit"
                test.cases="tck.dev.htmlunit.tests"
diff --git a/user/src/com/google/gwt/junit/JUnitShell.java b/user/src/com/google/gwt/junit/JUnitShell.java
index d365c7b..e4f1653 100644
--- a/user/src/com/google/gwt/junit/JUnitShell.java
+++ b/user/src/com/google/gwt/junit/JUnitShell.java
@@ -810,7 +810,7 @@
   /**
    * True if we are running the test in development mode.
    */
-  private boolean developmentMode = true;
+  private boolean developmentMode = false;
 
   /**
    * Used to make sure we don't start the runStyle more than once.
diff --git a/user/test/com/google/gwt/junit/JUnitShellTest.java b/user/test/com/google/gwt/junit/JUnitShellTest.java
index 97b672e..e5b8534 100644
--- a/user/test/com/google/gwt/junit/JUnitShellTest.java
+++ b/user/test/com/google/gwt/junit/JUnitShellTest.java
@@ -38,7 +38,7 @@
 
   public void testDefaultModuleUrl() throws Exception {
     parseGoodArgs();
-    assertEquals("http://localhost:1234/example/junit.html?gwt.codesvr=localhost:456",
+    assertEquals("http://localhost:1234/example/junit.html",
         shell.getModuleUrl("localhost", 1234, "example", 456));
   }