public Certificate loadSertificateFromFile(String path)
			throws FileNotFoundException, CertificateException {
		FileInputStream is = new FileInputStream(path);

		CertificateFactory cf = CertificateFactory.getInstance("X.509");
		java.security.cert.Certificate cert = cf.generateCertificate(is);
		return cert;
}
                
public byte[] sign(byte[] data) throws GeneralSecurityException, CMSException, IOException {
		  Security.addProvider(new BouncyCastleProvider());
		  CMSSignedDataGenerator generator = new CMSSignedDataGenerator();

		  X509V1CertificateGenerator certGen = new X509V1CertificateGenerator();
		  X509Certificate cert = (X509Certificate) loadSertificateFromFile("keyfile.pem");;

		  generator.addSigner(key, cert, CMSSignedDataGenerator.DIGEST_SHA1);
		  generator.addCertificatesAndCRLs(getCertStore(cert));
		  
		  CMSProcessable content = new CMSProcessableByteArray(data);
		  CMSSignedData signedData = generator.generate(content, true, "BC");
		  return signedData.getEncoded();
}

java.security.cert.CertificateException: Unable to initialize, java.io.IOException: DerInputStream.getLength(): lengthTag=58, too big.
	at sun.security.x509.X509CertImpl.<init>(Unknown Source)
	at sun.security.provider.X509Factory.engineGenerateCertificate(Unknown Source)
	at java.security.cert.CertificateFactory.generateCertificate(Unknown Source)
	at util.x509.loadSertificateFromFile(x509.java:47)