diff --git a/packages/block/src/header.ts b/packages/block/src/header.ts
index 0ae1eb5169d..2d4b400464e 100644
--- a/packages/block/src/header.ts
+++ b/packages/block/src/header.ts
@@ -669,7 +669,6 @@ export class BlockHeader {
       }
       return this.cache.hash
     }
-
     return keccak256(RLP.encode(this.raw()))
   }
 
diff --git a/packages/client/src/rpc/error-code.ts b/packages/client/src/rpc/error-code.ts
index 179a4ad5df7..6e6ccac48fa 100644
--- a/packages/client/src/rpc/error-code.ts
+++ b/packages/client/src/rpc/error-code.ts
@@ -6,3 +6,4 @@ export const METHOD_NOT_FOUND = -32601
 export const INVALID_PARAMS = -32602
 export const INTERNAL_ERROR = -32603
 export const TOO_LARGE_REQUEST = -38004
+export const UNSUPPORTED_FORK = -38005
diff --git a/packages/client/src/rpc/modules/engine.ts b/packages/client/src/rpc/modules/engine.ts
index ee61ae4580c..dfd3eea0bdc 100644
--- a/packages/client/src/rpc/modules/engine.ts
+++ b/packages/client/src/rpc/modules/engine.ts
@@ -13,7 +13,7 @@ import {
 
 import { PendingBlock } from '../../miner'
 import { short } from '../../util'
-import { INTERNAL_ERROR, INVALID_PARAMS, TOO_LARGE_REQUEST } from '../error-code'
+import { INTERNAL_ERROR, INVALID_PARAMS, TOO_LARGE_REQUEST, UNSUPPORTED_FORK } from '../error-code'
 import { CLConnectionManager, middleware as cmMiddleware } from '../util/CLConnectionManager'
 import { middleware, validators } from '../validation'
 
@@ -819,7 +819,7 @@ export class Engine {
     const ts = parseInt(params[0].timestamp)
     if (eip4844Timestamp === null || ts < eip4844Timestamp) {
       throw {
-        code: INVALID_PARAMS,
+        code: UNSUPPORTED_FORK,
         message: 'NewPayloadV{1|2} MUST be used before Cancun is activated',
       }
     }
diff --git a/packages/client/src/rpc/modules/eth.ts b/packages/client/src/rpc/modules/eth.ts
index 7a33acae30c..4b965a71aa1 100644
--- a/packages/client/src/rpc/modules/eth.ts
+++ b/packages/client/src/rpc/modules/eth.ts
@@ -131,6 +131,7 @@ const jsonRpcBlock = async (
     ...withdrawalsAttr,
     blobGasUsed: header.blobGasUsed,
     excessBlobGas: header.excessBlobGas,
+    parentBeaconBlockRoot: header.parentBeaconBlockRoot,
   }
 }
 
diff --git a/packages/client/src/service/txpool.ts b/packages/client/src/service/txpool.ts
index ca1098ff24b..b254f8e3dd6 100644
--- a/packages/client/src/service/txpool.ts
+++ b/packages/client/src/service/txpool.ts
@@ -246,9 +246,8 @@ export class TxPool {
 
     if (addedTx instanceof BlobEIP4844Transaction && existingTx instanceof BlobEIP4844Transaction) {
       const minblobGasFee =
-        (existingTx.maxFeePerblobGas *
-          (existingTx.maxFeePerblobGas * BigInt(MIN_GAS_PRICE_BUMP_PERCENT))) /
-        BigInt(100)
+        existingTx.maxFeePerblobGas +
+        (existingTx.maxFeePerblobGas * BigInt(MIN_GAS_PRICE_BUMP_PERCENT)) / BigInt(100)
       if (addedTx.maxFeePerblobGas < minblobGasFee) {
         throw new Error('replacement blob gas too low')
       }
diff --git a/packages/common/src/hardforks.ts b/packages/common/src/hardforks.ts
index 0acae08b5fe..59583547335 100644
--- a/packages/common/src/hardforks.ts
+++ b/packages/common/src/hardforks.ts
@@ -837,6 +837,6 @@ export const hardforks: HardforksDict = {
       'Next feature hardfork after the shanghai having proto-danksharding EIP 4844 blobs (still WIP hence not for production use), transient storage opcodes, parent beacon block root availability in EVM and selfdestruct only in same transaction',
     url: 'https://github.com/ethereum/execution-specs/blob/master/network-upgrades/mainnet-upgrades/cancun.md',
     status: Status.Final,
-    eips: [4844, 1153, 4788, 5656, 6780],
+    eips: [4844, 4788, 5656, 6780],
   },
 }