diff --git a/lib/model/txproposal.js b/lib/model/txproposal.js
index 7db3770..435ca01 100644
--- a/lib/model/txproposal.js
+++ b/lib/model/txproposal.js
@@ -341,7 +341,7 @@ TxProposal.prototype._addSignaturesToBitcoreTx = function(tx, signatures, xpub)
       var s = {
         inputIndex: i,
         signature: signature,
-        sigtype: bitcore.crypto.Signature.SIGHASH_ALL,
+        sigtype: bitcore.crypto.Signature.SIGHASH_ALL | bitcore.crypto.Signature.SIGHASH_FORKID,
         publicKey: pub,
       };
       tx.inputs[i].addSignature(tx, s);