diff --git a/teavm-jso-impl/src/main/java/org/teavm/jso/plugin/JS.java b/teavm-jso-impl/src/main/java/org/teavm/jso/plugin/JS.java
index ea8c3afdf..496759487 100644
--- a/teavm-jso-impl/src/main/java/org/teavm/jso/plugin/JS.java
+++ b/teavm-jso-impl/src/main/java/org/teavm/jso/plugin/JS.java
@@ -78,6 +78,7 @@ final class JS {
     public static native boolean unwrapBoolean(JSObject value);
 
     @InjectedBy(JSNativeGenerator.class)
+    @PluggableDependency(JSNativeGenerator.class)
     public static native String unwrapString(JSObject value);
 
     public static <T extends JSObject> JSArray<T> wrap(T[] array) {
diff --git a/teavm-tests/src/test/java/org/teavm/jso/test/JSOTest.java b/teavm-tests/src/test/java/org/teavm/jso/test/JSOTest.java
deleted file mode 100644
index 73ba3ca18..000000000
--- a/teavm-tests/src/test/java/org/teavm/jso/test/JSOTest.java
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
- *  Copyright 2015 Alexey Andreev.
- *
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- *
- *       http://www.apache.org/licenses/LICENSE-2.0
- *
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- */
-package org.teavm.jso.test;
-
-import static org.junit.Assert.*;
-import org.junit.Test;
-import org.teavm.jso.JSBody;
-import org.teavm.jso.JSObject;
-
-/**
- *
- * @author Alexey Andreev
- */
-public class JSOTest {
-    @Test
-    public void complexConstructorParenthesized() {
-        RegExp regexp = RegExp.create();
-        assertEquals(".", regexp.getSource());
-    }
-
-    @Test
-    public void externalMethodsResolved() {
-        int r = jsMethod(new Callback() {
-            @Override public int call() {
-                return 23;
-            }
-        });
-        assertEquals(23, r);
-    }
-
-    interface Callback extends JSObject {
-        int call();
-    }
-
-    @JSBody(params = "cb", script = "return cb.call();")
-    private static native int jsMethod(Callback cb);
-}
diff --git a/teavm-tests/src/test/java/org/teavm/jso/test/RegExp.java b/teavm-tests/src/test/java/org/teavm/jso/test/RegExp.java
deleted file mode 100644
index 6747fcecc..000000000
--- a/teavm-tests/src/test/java/org/teavm/jso/test/RegExp.java
+++ /dev/null
@@ -1,32 +0,0 @@
-/*
- *  Copyright 2015 Alexey Andreev.
- *
- *  Licensed under the Apache License, Version 2.0 (the "License");
- *  you may not use this file except in compliance with the License.
- *  You may obtain a copy of the License at
- *
- *       http://www.apache.org/licenses/LICENSE-2.0
- *
- *  Unless required by applicable law or agreed to in writing, software
- *  distributed under the License is distributed on an "AS IS" BASIS,
- *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- *  See the License for the specific language governing permissions and
- *  limitations under the License.
- */
-package org.teavm.jso.test;
-
-import org.teavm.jso.JSBody;
-import org.teavm.jso.JSObject;
-import org.teavm.jso.JSProperty;
-
-/**
- *
- * @author Alexey Andreev
- */
-public abstract class RegExp implements JSObject {
-    @JSProperty
-    public abstract String getSource();
-
-    @JSBody(params = {}, script = "return new RegExp();")
-    public static native RegExp create();
-}