diff --git a/rpc/rpc.go b/rpc/rpc.go
index 96137bb77..1a4237da5 100644
--- a/rpc/rpc.go
+++ b/rpc/rpc.go
@@ -12,7 +12,7 @@ import (
 	"strings"
 	"sync"
 
-	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 
 	"github.com/sammy007/open-ethereum-pool/util"
 )
@@ -177,7 +177,7 @@ func (r *RPCClient) GetBalance(address string) (*big.Int, error) {
 
 func (r *RPCClient) Sign(from string, s string) (string, error) {
 	hash := sha256.Sum256([]byte(s))
-	rpcResp, err := r.doPost(r.Url, "eth_sign", []string{from, common.ToHex(hash[:])})
+	rpcResp, err := r.doPost(r.Url, "eth_sign", []string{from, hexutil.Encode(hash[:])})
 	var reply string
 	if err != nil {
 		return reply, err
diff --git a/util/util.go b/util/util.go
index b4219c52e..bfcd600a5 100644
--- a/util/util.go
+++ b/util/util.go
@@ -8,6 +8,8 @@ import (
 
 	"github.com/ethereum/go-ethereum/common"
 	"github.com/ethereum/go-ethereum/common/math"
+	"github.com/ethereum/go-ethereum/common/hexutil"
+
 )
 
 var Ether = math.BigPow(10, 18)
@@ -35,7 +37,7 @@ func MakeTimestamp() int64 {
 func GetTargetHex(diff int64) string {
 	difficulty := big.NewInt(diff)
 	diff1 := new(big.Int).Div(pow256, difficulty)
-	return string(common.ToHex(diff1.Bytes()))
+	return string(hexutil.Encode(diff1.Bytes()))
 }
 
 func TargetHexToDiff(targetHex string) *big.Int {