diff --git a/jps/antLayout/src/jetbrains/antlayout/tasks/LayoutTask.java b/jps/antLayout/src/jetbrains/antlayout/tasks/LayoutTask.java
index d2308112a4d4..ac2419a528f7 100755
--- a/jps/antLayout/src/jetbrains/antlayout/tasks/LayoutTask.java
+++ b/jps/antLayout/src/jetbrains/antlayout/tasks/LayoutTask.java
@@ -33,6 +33,10 @@ public class LayoutTask extends Task {
         containers.add(container);
     }
 
+    public void addModule(IdeaModule module) {
+        containers.add(new FileSetContainer(module));
+    }
+
     public void addFileset(FileSet fileSet) {
         containers.add(new FileSetContainer(fileSet));
     }
diff --git a/jps/src/org/jetbrains/jps/idea/IdeaProjectLoader.groovy b/jps/src/org/jetbrains/jps/idea/IdeaProjectLoader.groovy
index 4536c49a435d..cceaca667b54 100644
--- a/jps/src/org/jetbrains/jps/idea/IdeaProjectLoader.groovy
+++ b/jps/src/org/jetbrains/jps/idea/IdeaProjectLoader.groovy
@@ -138,7 +138,7 @@ public class IdeaProjectLoader {
   }
 
   private NodeList loadProjectLibraries(Node librariesComponent, Project project, String projectBasePath) {
-    return librariesComponent?.library.each {Node libTag ->
+    return librariesComponent?.library?.each {Node libTag ->
       project.createLibrary(libTag."@name", libraryInitializer(libTag, projectBasePath, null))
     }
   }
diff --git a/jps/testData/overwriteTest/data/d1/x.txt b/jps/testData/overwriteTest/data/d1/x.txt
new file mode 100644
index 000000000000..562890baa53a
--- /dev/null
+++ b/jps/testData/overwriteTest/data/d1/x.txt
@@ -0,0 +1 @@
+d1
\ No newline at end of file
diff --git a/jps/testData/overwriteTest/data/d2/x.txt b/jps/testData/overwriteTest/data/d2/x.txt
new file mode 100644
index 000000000000..624c89d7c4d3
--- /dev/null
+++ b/jps/testData/overwriteTest/data/d2/x.txt
@@ -0,0 +1 @@
+d2
\ No newline at end of file
diff --git a/jps/testData/overwriteTest/dep/dep.iml b/jps/testData/overwriteTest/dep/dep.iml
new file mode 100644
index 000000000000..d5c074327501
--- /dev/null
+++ b/jps/testData/overwriteTest/dep/dep.iml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
+
diff --git a/jps/testData/overwriteTest/dep/src/a.xml b/jps/testData/overwriteTest/dep/src/a.xml
new file mode 100644
index 000000000000..a185e52cec98
--- /dev/null
+++ b/jps/testData/overwriteTest/dep/src/a.xml
@@ -0,0 +1 @@
+<root2/>
\ No newline at end of file
diff --git a/jps/testData/overwriteTest/overwriteTest.iml b/jps/testData/overwriteTest/overwriteTest.iml
new file mode 100644
index 000000000000..d5c074327501
--- /dev/null
+++ b/jps/testData/overwriteTest/overwriteTest.iml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module type="JAVA_MODULE" version="4">
+  <component name="NewModuleRootManager" inherit-compiler-output="true">
+    <exclude-output />
+    <content url="file://$MODULE_DIR$">
+      <sourceFolder url="file://$MODULE_DIR$/src" isTestSource="false" />
+    </content>
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>
+
diff --git a/jps/testData/overwriteTest/overwriteTest.ipr b/jps/testData/overwriteTest/overwriteTest.ipr
new file mode 100644
index 000000000000..96384495dfed
--- /dev/null
+++ b/jps/testData/overwriteTest/overwriteTest.ipr
@@ -0,0 +1,49 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ArtifactManager">
+    <artifact name="dirs">
+      <output-path>$PROJECT_DIR$/out/artifacts/dirs</output-path>
+      <root id="root">
+        <element id="dir-copy" path="$PROJECT_DIR$/data/d2" />
+        <element id="dir-copy" path="$PROJECT_DIR$/data/d1" />
+      </root>
+    </artifact>
+    <artifact name="classes">
+      <output-path>$PROJECT_DIR$/out/artifacts/classes</output-path>
+      <root id="root">
+        <element id="module-output" name="dep" />
+        <element id="module-output" name="overwriteTest" />
+      </root>
+    </artifact>
+  </component>
+  <component name="CompilerConfiguration">
+    <option name="DEFAULT_COMPILER" value="Javac" />
+    <resourceExtensions>
+      <entry name=".+\.(properties|xml|html|dtd|tld)" />
+      <entry name=".+\.(gif|png|jpeg|jpg)" />
+    </resourceExtensions>
+    <wildcardResourcePatterns>
+      <entry name="?*.properties" />
+      <entry name="?*.xml" />
+      <entry name="?*.gif" />
+      <entry name="?*.png" />
+      <entry name="?*.jpeg" />
+      <entry name="?*.jpg" />
+      <entry name="?*.html" />
+      <entry name="?*.dtd" />
+      <entry name="?*.tld" />
+      <entry name="?*.ftl" />
+    </wildcardResourcePatterns>
+    <annotationProcessing enabled="false" useClasspath="true" />
+  </component>
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/dep/dep.iml" filepath="$PROJECT_DIR$/dep/dep.iml" />
+      <module fileurl="file://$PROJECT_DIR$/overwriteTest.iml" filepath="$PROJECT_DIR$/overwriteTest.iml" />
+    </modules>
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_5" assert-keyword="true" jdk-15="true" project-jdk-name="1.6" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
+
diff --git a/jps/testData/overwriteTest/src/a.xml b/jps/testData/overwriteTest/src/a.xml
new file mode 100644
index 000000000000..8d3d60bcf499
--- /dev/null
+++ b/jps/testData/overwriteTest/src/a.xml
@@ -0,0 +1 @@
+<root1/>
\ No newline at end of file
diff --git a/jps/testSrc/org/jetbrains/jps/JpsBuildTestCase.groovy b/jps/testSrc/org/jetbrains/jps/JpsBuildTestCase.groovy
index 1695195745eb..17540cb57cbe 100644
--- a/jps/testSrc/org/jetbrains/jps/JpsBuildTestCase.groovy
+++ b/jps/testSrc/org/jetbrains/jps/JpsBuildTestCase.groovy
@@ -2,7 +2,9 @@ package org.jetbrains.jps
 
 import junit.framework.TestCase
 import org.codehaus.gant.GantBinding
-import org.jetbrains.jps.idea.IdeaProjectLoader;
+import org.jetbrains.jps.idea.IdeaProjectLoader
+import org.jetbrains.jps.util.FileSystemItem
+import org.jetbrains.jps.util.FileUtil;
 
 /**
  * @author nik
diff --git a/jps/testSrc/org/jetbrains/jps/OverwriteTest.groovy b/jps/testSrc/org/jetbrains/jps/OverwriteTest.groovy
new file mode 100644
index 000000000000..3f6dedefab9a
--- /dev/null
+++ b/jps/testSrc/org/jetbrains/jps/OverwriteTest.groovy
@@ -0,0 +1,27 @@
+package org.jetbrains.jps
+
+/**
+ * @author nik
+ */
+class OverwriteTest extends JpsBuildTestCase {
+  public void testOverwriteArtifacts() throws Exception {
+    doTest("testData/overwriteTest/overwriteTest.ipr", {}, {
+      dir("artifacts") {
+        dir("classes") {
+          file("a.xml", "<root2/>")
+        }
+        dir("dirs") {
+          file("x.txt", "d2")
+        }
+      }
+      dir("production") {
+        dir("dep") {
+          file("a.xml", "<root2/>")
+        }
+        dir("overwriteTest") {
+          file("a.xml", "<root1/>")
+        }
+      }
+    })
+  }
+}
diff --git a/jps/testSrc/org/jetbrains/jps/FileSystemItem.groovy b/jps/testSrc/org/jetbrains/jps/util/FileSystemItem.groovy
similarity index 98%
rename from jps/testSrc/org/jetbrains/jps/FileSystemItem.groovy
rename to jps/testSrc/org/jetbrains/jps/util/FileSystemItem.groovy
index 77e814f25164..f04a45049785 100644
--- a/jps/testSrc/org/jetbrains/jps/FileSystemItem.groovy
+++ b/jps/testSrc/org/jetbrains/jps/util/FileSystemItem.groovy
@@ -1,4 +1,4 @@
-package org.jetbrains.jps
+package org.jetbrains.jps.util
 
 import junit.framework.Assert
 
diff --git a/jps/testSrc/org/jetbrains/jps/FileUtil.groovy b/jps/testSrc/org/jetbrains/jps/util/FileUtil.groovy
similarity index 99%
rename from jps/testSrc/org/jetbrains/jps/FileUtil.groovy
rename to jps/testSrc/org/jetbrains/jps/util/FileUtil.groovy
index 5240dd97bd56..9af86d7a25c1 100644
--- a/jps/testSrc/org/jetbrains/jps/FileUtil.groovy
+++ b/jps/testSrc/org/jetbrains/jps/util/FileUtil.groovy
@@ -1,4 +1,4 @@
-package org.jetbrains.jps
+package org.jetbrains.jps.util
 
 /**
  * @author nik
diff --git a/jps/testSrc/org/jetbrains/jps/ZipUtil.groovy b/jps/testSrc/org/jetbrains/jps/util/ZipUtil.groovy
similarity index 98%
rename from jps/testSrc/org/jetbrains/jps/ZipUtil.groovy
rename to jps/testSrc/org/jetbrains/jps/util/ZipUtil.groovy
index ddbf5c10b22e..4f1227b840ad 100644
--- a/jps/testSrc/org/jetbrains/jps/ZipUtil.groovy
+++ b/jps/testSrc/org/jetbrains/jps/util/ZipUtil.groovy
@@ -1,4 +1,4 @@
-package org.jetbrains.jps
+package org.jetbrains.jps.util
 
 import java.util.zip.ZipEntry
 import java.util.zip.ZipFile