Native extension to unzip a file crash my air app

Hello,

I have a problem with a native extension for android

I want to unzip a file

my java code

File f = new File("my zip file");
File outputDir = new File ("output folder");
ZipHelper.unzip(f, outputDir);

and

import java.util.zip.*;
import java.io.*;
import java.util.Enumeration;
import org.apache.commons.io.IOUtils;
import android.util.Log;

public class ZipHelper
{
static public void unzip(File archive, File outputDir)
{
try {
Log.d("control","ZipHelper.unzip() - File: " + archive.getPath());
ZipFile zipfile = new ZipFile(archive);
for (Enumeration e = zipfile.entries(); e.hasMoreElements(); ) {
ZipEntry entry = (ZipEntry) e.nextElement();
unzipEntry(zipfile, entry, outputDir);
}
}
catch (Exception e) {
Log.d("control","ZipHelper.unzip() - Error extracting file " + archive+": "+ e);
}
}

static private void unzipEntry(ZipFile zipfile, ZipEntry entry, File outputDir) throws IOException
{
if (entry.isDirectory()) {
createDirectory(new File(outputDir, entry.getName()));
return;
}

File outputFile = new File(outputDir, entry.getName());
if (!outputFile.getParentFile().exists()){
createDirectory(outputFile.getParentFile());
}

Log.d("control","ZipHelper.unzipEntry() - Extracting: " + entry);
BufferedInputStream inputStream = new BufferedInputStream(zipfile.getInputStream(entry));
BufferedOutputStream outputStream = new BufferedOutputStream(new FileOutputStream(outputFile));

try {
IOUtils.copy(inputStream, outputStream);
}
catch (Exception e) {
Log.d("control","ZipHelper.unzipEntry() - Error: " + e);
}
finally {
outputStream.close();
inputStream.close();
}
}

static private void createDirectory(File dir)
{
Log.d("control","ZipHelper.createDir() - Creating directory: "+dir.getName());
if (!dir.exists()){
if(!dir.mkdirs()) throw new RuntimeException("Can't create directory "+dir);
}
else Log.d("control","ZipHelper.createDir() - Exists directory: "+dir.getName());
}
}

i copy the file commons-io-2.4.jar (I get at http://commons.apache.org/proper/commons-io/download_io.cgi) in the lib folder of eclipse.

in a native android app, this code work fine

in a native extension for air, my air app crash

LogCat in eclipse return

NoClassDefFoundError: org.apache.comons.io.IOUtils.copy

IOUtils class is not in commons-io-2.4.jar ???

thanks