private SecurityHeaderElement createSignature(final PublicKey pubKey,final Key signingKey,final SAMLToken samlToken,final NamespaceContextEx nsContext)throws WSTrustException{
try{
final JAXBSignatureFactory signatureFactory = JAXBSignatureFactory.newInstance();
final C14NMethodParameterSpec spec = null;
final CanonicalizationMethod canonicalMethod =
signatureFactory.newCanonicalizationMethod(CanonicalizationMethod.EXCLUSIVE,spec);
DigestMethod digestMethod;
digestMethod = signatureFactory.newDigestMethod(DigestMethod.SHA1, null);
SignatureMethod signatureMethod;
signatureMethod = signatureFactory.newSignatureMethod(SignatureMethod.RSA_SHA1, null);