diff --git a/build.xml b/build.xml
index cab8bd8cd2b..1438501c068 100644
--- a/build.xml
+++ b/build.xml
@@ -284,6 +284,26 @@
         <arg value="core/builtins/native"/>
         <arg value="core/builtins/src"/>
       </java>
+
+      <if>
+        <isfalse value="${bootstrap.build.no.tests}"/>
+        <then>
+          <cleandir dir="${output}/renameImportJet"/>
+          <kotlinc output="${output}/renameImportJet">
+            <src path="renameImportJet.kt"/>
+            <classpath refid="classpath"/>
+          </kotlinc>
+          <java classname="_DefaultPackage" failonerror="true" fork="true">
+            <classpath>
+              <pathelement location="${output}/renameImportJet"/>
+              <path refid="classpath"/>
+            </classpath>
+            <assertions>
+              <enable/>
+            </assertions>
+          </java>
+        </then>
+      </if>
     </target>
 
     <macrodef name="pack_compiler">
diff --git a/renameImportJet.kt b/renameImportJet.kt
new file mode 100644
index 00000000000..25f4f988002
--- /dev/null
+++ b/renameImportJet.kt
@@ -0,0 +1,34 @@
+import java.io.File
+import com.intellij.util.Processor
+import com.intellij.openapi.util.io.FileUtil
+import java.util.ArrayList
+
+fun main(args: Array<String>) {
+    println("renameImportJet")
+
+    fun processFile(file: File) {
+        if (!file.getName().endsWith(".java") || file.isDirectory()) return
+
+        val lines = ArrayList<String>()
+        var rewrite = false
+        file.reader().forEachLine { line ->
+            if (line.startsWith("import jet.") && !line.startsWith("import jet.runtime.typeinfo"))  {
+                lines.add("import kotlin." + line.substring("import jet.".length))
+                rewrite = true
+            }
+            else {
+                lines.add(line)
+            }
+        }
+
+        if (rewrite) {
+            println("renaming imports in $file")
+            file.writeText(lines reduce { (a, b) -> "$a\n$b" })
+        }
+    }
+
+    val processor = Processor<File> { if (it != null) processFile(it); true }
+    val directoryFilter = Processor<File> { it?.getName() != "testData" }
+
+    FileUtil.processFilesRecursively(File("."), processor, directoryFilter)
+}