diff --git a/CHANGELOG.md b/CHANGELOG.md
index 68ebb2a..0158389 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,4 +1,7 @@
 # Changelog
+## [4.0.1] - 2024-12-16
+### fix
+-`signMessage` on walletconnect now verifies as valid on react walletConnect testing app
 
 ## [4.0.0] - 2024-12-12
 ### Breaking Changes
diff --git a/examples/basics/verify-signatures.ts b/examples/basics/verify-signatures.ts
new file mode 100644
index 0000000..15c7507
--- /dev/null
+++ b/examples/basics/verify-signatures.ts
@@ -0,0 +1,82 @@
+import * as dotenv from 'dotenv';
+import { generateModularSDKInstance } from '../helpers/sdk-helper';
+import { Address, createPublicClient, Hex, http } from 'viem';
+import { sepolia } from 'viem/chains';
+
+dotenv.config();
+
+// tsx examples/basics/get-address.ts
+async function main() {
+  const bundlerApiKey = 'eyJvcmciOiI2NTIzZjY5MzUwOTBmNzAwMDFiYjJkZWIiLCJpZCI6IjMxMDZiOGY2NTRhZTRhZTM4MGVjYjJiN2Q2NDMzMjM4IiwiaCI6Im11cm11cjEyOCJ9';
+
+  // initializating sdk...
+  const modularSdk = generateModularSDKInstance(
+    process.env.WALLET_PRIVATE_KEY as string,
+     Number(process.env.CHAIN_ID), bundlerApiKey);
+
+  // get EtherspotWallet address...
+  const address: string = await modularSdk.getCounterFactualAddress();
+  console.log('\x1b[33m%s\x1b[0m', `EtherspotWallet address: ${address}`);
+
+  const typedData = {
+    domain: {
+    name: 'EtherspotModular',
+    version: '1.0.0',
+    chainId: 11155111,
+    verifyingContract: `0x${address.slice(2)}` as Address,
+  },
+  types: {
+    Person: [
+      { name: 'name', type: 'string' },
+      { name: 'wallet', type: 'address' },
+    ],
+    Mail: [
+      { name: 'from', type: 'Person' },
+      { name: 'to', type: 'Person' },
+      { name: 'contents', type: 'string' },
+    ],
+  },
+  primaryType: 'Mail',
+  message: {
+    from: {
+      name: 'Cow',
+      wallet: '0xCD2a3d9F938E13CD947Ec05AbC7FE734Df8DD826',
+    },
+    to: {
+      name: 'Bob',
+      wallet: '0xbBbBBBBbbBBBbbbBbbBbbbbBBbBbbbbBbBbbBBbB',
+    },
+    contents: 'Hello, Bob!',
+  },
+  }
+
+  const signTypedData = await modularSdk.signTypedData(typedData);
+  const sign = await modularSdk.signMessage({message: 'Hello'})
+
+  console.log('signature: ', sign, signTypedData);
+
+  const publicClient = createPublicClient({
+    chain: sepolia,
+    transport: http(`https://testnet-rpc.etherspot.io/v2/11155111?api-key=${bundlerApiKey}`),
+  })
+
+	console.log(await publicClient.verifyMessage({
+		address: address as Address,
+		signature: sign as Hex,
+    message: 'Hello'
+	}))
+
+  console.log(await publicClient.verifyTypedData({
+    address: address as Address,
+    domain: typedData.domain,
+    types: typedData.types,
+    primaryType: 'Mail',
+    message: typedData.message,
+    signature: signTypedData as Hex,
+  }))
+
+}
+
+main()
+  .catch(console.error)
+  .finally(() => process.exit());
diff --git a/package-lock.json b/package-lock.json
index 1a0b787..9f8a08c 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@etherspot/modular-sdk",
-  "version": "4.0.0",
+  "version": "4.0.1",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "@etherspot/modular-sdk",
-      "version": "4.0.0",
+      "version": "4.0.1",
       "license": "MIT",
       "dependencies": {
         "@lifi/sdk": "2.5.0",
diff --git a/package.json b/package.json
index 5f78a34..aaa0195 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@etherspot/modular-sdk",
-  "version": "4.0.0",
+  "version": "4.0.1",
   "description": "Etherspot Modular SDK - build with ERC-7579 smart accounts modules",
   "keywords": [
     "ether",
diff --git a/src/sdk/common/OperationUtils.ts b/src/sdk/common/OperationUtils.ts
index 3d66364..e6b87a1 100644
--- a/src/sdk/common/OperationUtils.ts
+++ b/src/sdk/common/OperationUtils.ts
@@ -1,13 +1,17 @@
 import { resolveProperties } from './utils';
 import { BaseAccountUserOperationStruct } from '../types/user-operation-types';
 import { toHex } from 'viem';
+import { BigNumber } from '../types/bignumber';
 
 export function toJSON(op: Partial<BaseAccountUserOperationStruct>): Promise<any> {
   return resolveProperties(op).then((userOp) =>
     Object.keys(userOp)
       .map((key) => {
         let val = (userOp as any)[key];
-        if (typeof val !== 'string' || !val.startsWith('0x')) {
+        if (typeof val === 'object' && BigNumber.isBigNumber(val)) {
+          val = val.toHexString()
+        }
+        else if (typeof val !== 'string' || !val.startsWith('0x')) {
           val = toHex(val);
         }
         return [key, val];
diff --git a/src/sdk/wallet/providers/key.wallet-provider.ts b/src/sdk/wallet/providers/key.wallet-provider.ts
index 351b5aa..3f14cbc 100644
--- a/src/sdk/wallet/providers/key.wallet-provider.ts
+++ b/src/sdk/wallet/providers/key.wallet-provider.ts
@@ -1,4 +1,4 @@
-import { Hash, Hex, TransactionRequest, WalletClient, createWalletClient, http, concat, Address, encodeAbiParameters, parseAbiParameters } from 'viem';
+import { Hash, Hex, TransactionRequest, WalletClient, createWalletClient, http, concat, Address, encodeAbiParameters, parseAbiParameters, hashMessage, toBytes } from 'viem';
 import { MessagePayload, WalletProvider } from './interfaces';
 import { privateKeyToAccount } from 'viem/accounts';
 import { Networks } from '../../network/constants';
@@ -24,7 +24,7 @@ export class KeyWalletProvider implements WalletProvider {
 
   async signMessage(message: string, validatorAddress?: Address, factoryAddress?: Address, initCode?: Hex): Promise<string> {
     const signature = await this.wallet.signMessage({
-      message: message,
+      message: {raw: toBytes(hashMessage({raw : toBytes(message)}))},
       account: this.wallet.account
     })
     if (initCode !== '0x') {