Java Security

Hi, I need some help Tryng to crypt and decrypt a String using AES/ECB/PKCS5Padding

I paste my code below

Crypt

 Cipher cipher;
         byte[] pass=new byte[]{1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}; // just for example
        SecretKeySpec key = new SecretKeySpec(pass, "AES");
        cipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
        cipher.init(Cipher.ENCRYPT_MODE, key);         
        byte[] utf8 = da_cifrare.getBytes("utf-8");
        byte[] enc = cipher.doFinal(utf8);
        String cifrata =new String (Base64.encodeBase64(enc));
        return cifrata;

And on the other side Decrypt

Cipher decipher;
           byte[] pass=new byte[]{1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}; // just for example
           SecretKeySpec key = new SecretKeySpec(pass, "AES");
           decipher = Cipher.getInstance("AES/ECB/PKCS5Padding");
           decipher.init(Cipher.DECRYPT_MODE, key);  
           byte[] buf =Base64.decodeBase64(da_decifrare.getBytes("utf-8"));
           byte[] recoveredBytes = decipher.doFinal(buf); 
           String in_chiaro = new String (recoveredBytes,"utf-8"); 
           return (in_chiaro);

I'm getting Bad padding exception when I try to Decrypt, any ideas ??