diff --git a/pytrustnfe/nfe/__init__.py b/pytrustnfe/nfe/__init__.py
index 0c2b0a7..824284b 100644
--- a/pytrustnfe/nfe/__init__.py
+++ b/pytrustnfe/nfe/__init__.py
@@ -10,6 +10,7 @@ from pytrustnfe.xml import render_xml
 from pytrustnfe.utils import CabecalhoSoap
 from pytrustnfe.utils import gerar_chave, ChaveNFe
 from pytrustnfe.Servidores import localizar_url
+import re
 
 
 def _build_header(**kwargs):
@@ -31,7 +32,9 @@ def _generate_nfe_id(**kwargs):
             'codigo': item['infNFe']['ide']['cNF'],
         }
         chave = ChaveNFe(**vals)
-        item['infNFe']['Id'] = gerar_chave(chave, 'NFe')
+        chave_nfe = gerar_chave(chave, 'NFe')
+        item['infNFe']['Id'] = chave_nfe
+        item['infNFe']['ide']['cDV'] = chave_nfe[len(chave_nfe) - 1:]
 
 
 def _send(certificado, method, **kwargs):
@@ -39,13 +42,15 @@ def _send(certificado, method, **kwargs):
 
     xml = render_xml(path, '%s.xml' % method, **kwargs)
     xml = '<!DOCTYPE NFe [<!ATTLIST infNFe Id ID #IMPLIED>]>' + xml
-
+    xml = xml.replace('\n', '')
     pfx_path = certificado.save_pfx()
     signer = Assinatura(pfx_path, certificado.password)
-    xml_signed = signer.assina_xml(xml, kwargs['NFes'][0]['infNFe']['Id'])
+    xml_signed = signer.assina_xml_nota(xml, kwargs['NFes'][0]['infNFe']['Id'])
 
     xml_signed = xml_signed.replace(
         '\n<!DOCTYPE NFe [\n<!ATTLIST infNFe Id ID #IMPLIED>\n]>\n', '')
+    print xml_signed
+    xml_signed = xml_signed.replace('\n', '')
 
     url = localizar_url(0,  'RS')
     cabecalho = _build_header(**kwargs)
diff --git a/pytrustnfe/nfe/assinatura.py b/pytrustnfe/nfe/assinatura.py
index 81831fc..ad531b0 100644
--- a/pytrustnfe/nfe/assinatura.py
+++ b/pytrustnfe/nfe/assinatura.py
@@ -86,3 +86,54 @@ class Assinatura(object):
         finally:
             doc_xml.freeDoc()
             # self._finalizar_cripto()
+
+    def assina_xml_nota(self, xml, reference):
+        self._checar_certificado()
+        self._inicializar_cripto()
+        try:
+            doc_xml = libxml2.parseMemory(
+                xml, len(xml))
+            signNode = xmlsec.TmplSignature(doc_xml,
+                                            xmlsec.transformInclC14NId(),
+                                            xmlsec.transformRsaSha1Id(), None)
+            doc_xml.getRootElement().get_last().addChild(signNode)
+            refNode = signNode.addReference(xmlsec.transformSha1Id(),
+                                            None, '#' + str(reference), None)
+
+            refNode.addTransform(xmlsec.transformEnvelopedId())
+            refNode.addTransform(xmlsec.transformInclC14NId())
+            keyInfoNode = signNode.ensureKeyInfo()
+            keyInfoNode.addX509Data()
+
+            dsig_ctx = xmlsec.DSigCtx()
+            chave = xmlsec.cryptoAppKeyLoad(filename=str(self.arquivo),
+                                            format=xmlsec.KeyDataFormatPkcs12,
+                                            pwd=str(self.senha),
+                                            pwdCallback=None,
+                                            pwdCallbackCtx=None)
+
+            dsig_ctx.signKey = chave
+            dsig_ctx.sign(signNode)
+
+            status = dsig_ctx.status
+            dsig_ctx.destroy()
+
+            if status != xmlsec.DSigStatusSucceeded:
+                raise RuntimeError(
+                    'Erro ao realizar a assinatura do arquivo; status: "' +
+                    str(status) +
+                    '"')
+
+            xpath = doc_xml.xpathNewContext()
+            xpath.xpathRegisterNs('sig', NAMESPACE_SIG)
+            certificados = xpath.xpathEval(
+                '//sig:X509Data/sig:X509Certificate')
+            for i in range(len(certificados) - 1):
+                certificados[i].unlinkNode()
+                certificados[i].freeNode()
+
+            xml = doc_xml.serialize()
+            return xml
+        finally:
+            doc_xml.freeDoc()
+            # self._finalizar_cripto()