diff --git a/oidc_provider/lib/utils/token.py b/oidc_provider/lib/utils/token.py
index 5d6e745..4db124b 100644
--- a/oidc_provider/lib/utils/token.py
+++ b/oidc_provider/lib/utils/token.py
@@ -56,9 +56,7 @@ def encode_id_token(payload):
     key_string = get_rsa_key().encode('utf-8')
     keys = [ RSAKey(key=importKey(key_string), kid=md5(key_string).hexdigest()) ]
     _jws = JWS(payload, alg='RS256')
-    _jwt = _jws.sign_compact(keys)
-
-    return _jwt.decode('utf-8')
+    return _jws.sign_compact(keys)
 
 
 def create_token(user, client, id_token_dic, scope):
diff --git a/setup.py b/setup.py
index 1023408..ed57e42 100644
--- a/setup.py
+++ b/setup.py
@@ -37,10 +37,10 @@ setup(
         'Topic :: Internet :: WWW/HTTP :: Dynamic Content',
     ],
     tests_require=[
-        'pyjwkest==1.0.1',
+        'pyjwkest>=1.0.3,<1.1',
     ],
 
     install_requires=[
-        'pyjwkest==1.0.1',
+        'pyjwkest>=1.0.3,<1.1',
     ],
 )