diff --git a/ant/ant.iml b/ant/ant.iml
index 4548c995447..c7770d1e52b 100644
--- a/ant/ant.iml
+++ b/ant/ant.iml
@@ -9,5 +9,6 @@
     <orderEntry type="sourceFolder" forTests="false" />
     <orderEntry type="library" name="ant-1.7" level="project" />
     <orderEntry type="library" name="kotlin-runtime" level="project" />
+    <orderEntry type="module" module-name="preloader" />
   </component>
 </module>
\ No newline at end of file
diff --git a/ant/src/org/jetbrains/jet/buildtools/ant/KotlinCompilerBaseTask.kt b/ant/src/org/jetbrains/jet/buildtools/ant/KotlinCompilerBaseTask.kt
index db6c7e94306..d3da0cea4d4 100644
--- a/ant/src/org/jetbrains/jet/buildtools/ant/KotlinCompilerBaseTask.kt
+++ b/ant/src/org/jetbrains/jet/buildtools/ant/KotlinCompilerBaseTask.kt
@@ -25,13 +25,13 @@ import org.apache.tools.ant.types.Commandline
 import java.io.PrintStream
 import org.apache.tools.ant.AntClassLoader
 import java.lang.ref.SoftReference
-import org.apache.tools.ant.Project
+import org.jetbrains.jet.preloading.ClassPreloadingUtils
 import java.net.JarURLConnection
 
 object CompilerClassLoaderHolder {
     private var classLoaderRef = SoftReference<ClassLoader?>(null)
 
-    synchronized fun getOrCreateClassLoader(project: Project?): ClassLoader {
+    synchronized fun getOrCreateClassLoader(): ClassLoader {
         val cached = classLoaderRef.get()
         if (cached != null) return cached
 
@@ -49,7 +49,7 @@ object CompilerClassLoaderHolder {
             throw IllegalStateException("kotlin-compiler.jar is not found in the directory of Kotlin Ant task")
         }
 
-        val classLoader = AntClassLoader(myLoader, project, Path(project, compilerJarPath.path), /* parentFirst = */ false)
+        val classLoader = ClassPreloadingUtils.preloadClasses(listOf(compilerJarPath), 4096, myLoader, null)
         classLoaderRef = SoftReference(classLoader)
 
         return classLoader
@@ -112,7 +112,7 @@ public abstract class KotlinCompilerBaseTask : Task() {
     final override fun execute() {
         fillArguments()
 
-        val compilerClass = CompilerClassLoaderHolder.getOrCreateClassLoader(project).loadClass(compilerFqName)
+        val compilerClass = CompilerClassLoaderHolder.getOrCreateClassLoader().loadClass(compilerFqName)
         val compiler = compilerClass.newInstance()
         val exec = compilerClass.getMethod("execFullPathsInMessages", javaClass<PrintStream>(), javaClass<Array<String>>())
 
diff --git a/build.xml b/build.xml
index 84cb1d0f0e9..a694bdde5ef 100644
--- a/build.xml
+++ b/build.xml
@@ -641,7 +641,8 @@
             <compilerarg value="-Xlint:all"/>
             <classpath>
                 <file file="${kotlin-home}/lib/${compiler.manifest.class.path}"/>
-                <fileset dir="${dependencies.dir}/ant-1.7/lib" includes="ant.jar"/>
+                <pathelement location="${dependencies.dir}/ant-1.7/lib/ant.jar"/>
+                <pathelement location="${kotlin-home}/lib/kotlin-preloader.jar"/>
             </classpath>
         </javac2>
 
@@ -657,7 +658,7 @@
                 <attribute name="Implementation-Title" value="${manifest.impl.title.kotlin.compiler.ant.task}"/>
                 <attribute name="Implementation-Version" value="${build.number}"/>
 
-                <attribute name="Class-Path" value="${compiler.manifest.class.path}"/>
+                <attribute name="Class-Path" value="${compiler.manifest.class.path} kotlin-preloader.jar"/>
             </manifest>
         </jar>
     </target>