Problem med 3DES-dekryptering (JCE)

Jeg har lavet en lille java-applikation der (de)kryptere tekst-filer med java-packagen JCE vha. 3DES.

Applikationen krypterer tekst-filerne umiddelbart korrekt men kan ikke dekryptere filerne.

Forneden er fejlbesked, kildekode samt filen - "z.1" - der krypteres:

/Kenneth

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[Fejlbesked]

Exception in thread "main" java.security.InvalidKeyException: requires PBE param
eters
        at com.sun.crypto.provider.PBEWithMD5AndDESCipher.engineInit(DashoA12275
)
        at javax.crypto.Cipher.a(DashoA12275)
        at javax.crypto.Cipher.a(DashoA12275)
        at javax.crypto.Cipher.init(DashoA12275)
        at javax.crypto.Cipher.init(DashoA12275)
        at TripleDES.crypt(TripleDES.java:20)
        at TripleDES.decrypt(TripleDES.java:45)
        at TripleDES.main(TripleDES.java:49)
Caused by: java.security.InvalidAlgorithmParameterException: Parameters missing
        at com.sun.crypto.provider.SunJCE_ae.a(DashoA12275)
        at com.sun.crypto.provider.PBEWithMD5AndDESCipher.engineInit(DashoA12275
)
        ... 8 more

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[Kildekode]

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.Security;
import javax.crypto.*;
import javax.crypto.spec.*;

public class TripleDES {

    private static void crypt(int mode, String fromname, String toname, String key) throws Exception {
    Security.addProvider(new com.sun.crypto.provider.SunJCE());

    PBEKeySpec sPBEKey = new PBEKeySpec(key.toCharArray());
    SecretKeyFactory sKeyFactory = SecretKeyFactory.getInstance("PBEWithMD5AndTripleDES");
    SecretKey myTripleDesKey = sKeyFactory.generateSecret(sPBEKey);

    Cipher cipher = Cipher.getInstance(myTripleDesKey.getAlgorithm());

    cipher.init(mode,myTripleDesKey);

    InputStream is = new FileInputStream(fromname);
    OutputStream os = new FileOutputStream(toname);
    byte[] b = new byte[10000];
    int n;
    while((n = is.read(b)) >= 0) {
        byte[] b2;
        if(n < b.length) {
            b2 = cipher.doFinal(b, 0, n);
        } else {
            b2 = cipher.update(b, 0, n);
        }
        os.write(b2, 0, b2.length); 
        System.out.println(n + " " + b2.length);
    }
    is.close();
    os.close();
    }

    public static void encrypt(String fromname, String toname, String key) throws Exception {
    crypt(Cipher.ENCRYPT_MODE, fromname, toname, key);
    }

    public static void decrypt(String fromname, String toname, String key) throws Exception {
    crypt(Cipher.DECRYPT_MODE, fromname, toname, key);
    }
    public static void main(String[] args) throws Exception {
    encrypt("C:\\z.1", "C:\\z.2", "Top hemmeligt kodeord");
    decrypt("C:\\z.2", "C:\\z.3", "Top hemmeligt kodeord");
    }
}

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[Filen "z.1"]

test
test1

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