Create a token from the psecio/jwt package with encoding, copy over the secrets, encoding, etc and then apply the token.

jwt-decode.js

var jwt    = require('jsonwebtoken'),
    crypto = require('crypto')

var token  = '';
var cypher = 'aes-256-cbc';
var iv     = '1234567812345678';
var key    = 'my-encryption-key';
var secret = 'example_key';

// it comes over encrypted, so we have to get it all cleaned up
var decode = function(token, callback) {
    token = token.split('.');

    var claims = token[1];
    if (claims.length % 4 != 0) {
        claims += ('===').slice(0, 4 - (claims.length % 4));
    }
    claims = claims .replace(/-/g, '+').replace(/_/g, '/');
    // they were double base64 encoded... watch out :)
    // this is the psecio jwt library, it ultimately encodes the claims twice
    // since the encryption does it first and then the encoder does it a second
    // time.
    claims = new Buffer(claims, 'base64');
    claims = new Buffer(claims.toString('utf8'), 'base64');

    var decipher = crypto.createDecipheriv(cypher, new Buffer(key, 'ascii'), new Buffer(iv, 'ascii'));
    var decoded = Buffer.concat([
        decipher.update(claims),
        decipher.final()
    ]);

    console.log(decoded.toString('utf8'));
    token[1] = decoded.toString('base64');
    token[1] = token[1].replace(/\+/g, '-').replace(/\//g, '_').replace(/\=+$/, '');
    token = token.join('.');
    callback(token);
};

decode(token, function(token) {
    console.log(token);
    console.log(jwt.decode(token));
    jwt.verify(token, secret, function(err, decoded) {
        console.log(err);
        console.log(decoded);
    });
});

package.json

{
  "dependencies": {
    "jsonwebtoken": "^1.1.2"
  }
}