diff --git a/clients/py/sapphirepy/envelope.py b/clients/py/sapphirepy/envelope.py
index b78ddd3a..5ef90bf1 100644
--- a/clients/py/sapphirepy/envelope.py
+++ b/clients/py/sapphirepy/envelope.py
@@ -97,7 +97,7 @@ def encrypt(self, plaintext: bytes):
         }
         return cbor2.dumps(envelope, canonical=True)
 
-    def encrypt_envelope(self, plaintext: bytes):
+    def make_envelope(self, plaintext: bytes):
         ciphertext, nonce = self._encrypt_calldata(plaintext)
         envelope = {
             'body': {
diff --git a/clients/py/sapphirepy/sapphire.py b/clients/py/sapphirepy/sapphire.py
index 27f4babe..b3189197 100644
--- a/clients/py/sapphirepy/sapphire.py
+++ b/clients/py/sapphirepy/sapphire.py
@@ -77,7 +77,7 @@ def _encrypt_tx_params(pk: CalldataPublicKey,
                        params: tuple[TxParams],
                        method,
                        web3: Web3,
-                       account: LocalAccount) -> TransactionCipher:
+                       account: Optional[LocalAccount]) -> TransactionCipher:
     c = TransactionCipher(peer_pubkey=pk['key'], peer_epoch=pk['epoch'])
     data = params[0]['data']
     if isinstance(data, bytes):
@@ -91,12 +91,12 @@ def _encrypt_tx_params(pk: CalldataPublicKey,
     encrypted_data = c.encrypt(data_bytes)
 
     if params[0]['from'] and method == 'eth_call':
-        data_pack = _new_signed_call_data_pack(c.encrypt_envelope(data_bytes),
+        assert account is not None, 'Account must be provided for encrypted calls!'
+        data_pack = _new_signed_call_data_pack(c.make_envelope(data_bytes),
                                                data_bytes,
                                                params,
                                                web3,
                                                account)
-        data_pack['signature'] = bytes(data_pack['signature'])
         params[0]['data'] = cbor2.dumps(data_pack, canonical=True)
     else:
         params[0]['data'] = HexStr('0x' + hexlify(encrypted_data).decode('ascii'))
@@ -111,7 +111,7 @@ def _new_signed_call_data_pack(encrypted_data: dict,
                                account: LocalAccount) -> dict:
     # Update params with default values, these get used outside the scope of this function
     params[0]['gas'] = params[0].get('gas', DEFAULT_GAS_LIMIT)
-    params[0]['gasPrice'] = params[0].get('gasPrice', DEFAULT_GAS_PRICE)
+    params[0]['gasPrice'] = params[0].get('gasPrice', web3.to_wei(DEFAULT_GAS_PRICE, 'wei'))
 
     domain_data = {
         "name": "oasis-runtime-sdk/evm: signed query",
@@ -142,7 +142,7 @@ def _new_signed_call_data_pack(encrypted_data: dict,
             {"name": "blockRange", "type": "uint64"},
         ],
     }
-    nonce = web3.eth.get_transaction_count(params[0]['from'])
+    nonce = web3.eth.get_transaction_count(web3.to_checksum_address(params[0]['from']))
     block_number = web3.eth.block_number
     block_hash = web3.eth.get_block(block_number-1)['hash'].hex()
     msg_data = {
@@ -182,13 +182,13 @@ def _new_signed_call_data_pack(encrypted_data: dict,
     data_pack= {
         'data': encrypted_data,
         'leash': leash,
-        'signature': signed_msg['signature'],
+        'signature': bytes(signed_msg['signature']),
     }
     return data_pack
 
 
 def construct_sapphire_middleware(
-        account: LocalAccount = None
+        account: Optional[LocalAccount] = None
 ) -> Middleware:
     """
     Construct a Sapphire middleware for Web3.py.
@@ -264,7 +264,7 @@ def middleware(method: RPCEndpoint, params: Any) -> RPCResponse:
     return sapphire_middleware
 
 
-def wrap(w3: Web3, account: LocalAccount = None):
+def wrap(w3: Web3, account: Optional[LocalAccount] = None):
     """
     Adds the Sapphire transaction encryption middleware to a Web3.py provider.
 
diff --git a/clients/py/sapphirepy/tests/test_e2e.py b/clients/py/sapphirepy/tests/test_e2e.py
index fe27b43b..a8d32faf 100644
--- a/clients/py/sapphirepy/tests/test_e2e.py
+++ b/clients/py/sapphirepy/tests/test_e2e.py
@@ -56,6 +56,7 @@ def setUp(self):
         w3 = Web3(Web3.HTTPProvider('http://localhost:8545'))
         # w3 = Web3(Web3.HTTPProvider('https://testnet.sapphire.oasis.io'))
         w3.middleware_onion.add(construct_sign_and_send_raw_middleware(account))
+        self.w3_no_signer = Web3(Web3.HTTPProvider('http://localhost:8545'))
         self.w3 = w3 = sapphire.wrap(w3, account)
 
         w3.eth.default_account = account.address
@@ -67,6 +68,7 @@ def setUp(self):
         tx_receipt = w3.eth.wait_for_transaction_receipt(tx_hash)
 
         self.greeter = w3.eth.contract(address=tx_receipt['contractAddress'], abi=iface['abi'])
+        self.greeter_no_signer = self.w3_no_signer.eth.contract(address=tx_receipt['contractAddress'], abi=iface['abi'])
 
     def test_viewcall_revert_custom(self):
         with self.assertRaises(ContractCustomError) as cm:
@@ -87,6 +89,11 @@ def test_viewcall(self):
     def test_viewcall_only_owner(self):
         self.assertEqual(self.greeter.functions.greetOnlyOwner().call(), 'Hello')
 
+    def test_viewcall_only_owner_no_signer(self):
+        with self.assertRaises(ContractLogicError) as cm:
+            self.greeter_no_signer.functions.greetOnlyOwner().call()
+        self.assertEqual(cm.exception.message, 'execution reverted: Only owner can call this function')
+
     def test_transaction(self):
         w3 = self.w3
         greeter = self.greeter
diff --git a/clients/py/sapphirepy/tests/testdata/Greeter.abi b/clients/py/sapphirepy/tests/testdata/Greeter.abi
new file mode 100644
index 00000000..cfbd2b24
--- /dev/null
+++ b/clients/py/sapphirepy/tests/testdata/Greeter.abi
@@ -0,0 +1 @@
+[{"inputs": [], "stateMutability": "nonpayable", "type": "constructor"}, {"inputs": [{"internalType": "string", "name": "blah", "type": "string"}], "name": "MyCustomError", "type": "error"}, {"anonymous": false, "inputs": [{"indexed": false, "internalType": "string", "name": "g", "type": "string"}], "name": "Greeting", "type": "event"}, {"inputs": [], "name": "blah", "outputs": [], "stateMutability": "nonpayable", "type": "function"}, {"inputs": [], "name": "greet", "outputs": [{"internalType": "string", "name": "", "type": "string"}], "stateMutability": "view", "type": "function"}, {"inputs": [], "name": "greetOnlyOwner", "outputs": [{"internalType": "string", "name": "", "type": "string"}], "stateMutability": "view", "type": "function"}, {"inputs": [], "name": "greeting", "outputs": [{"internalType": "string", "name": "", "type": "string"}], "stateMutability": "view", "type": "function"}, {"inputs": [], "name": "owner", "outputs": [{"internalType": "address", "name": "", "type": "address"}], "stateMutability": "view", "type": "function"}, {"inputs": [], "name": "revertWithCustomError", "outputs": [], "stateMutability": "pure", "type": "function"}, {"inputs": [], "name": "revertWithReason", "outputs": [], "stateMutability": "pure", "type": "function"}, {"inputs": [{"internalType": "string", "name": "_greeting", "type": "string"}], "name": "setGreeting", "outputs": [], "stateMutability": "nonpayable", "type": "function"}]
\ No newline at end of file
diff --git a/clients/py/sapphirepy/tests/testdata/Greeter.bin b/clients/py/sapphirepy/tests/testdata/Greeter.bin
new file mode 100644
index 00000000..cf9ef436
--- /dev/null
+++ b/clients/py/sapphirepy/tests/testdata/Greeter.bin
@@ -0,0 +1 @@
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\ No newline at end of file