diff --git a/controller/tests/transaction.rs b/controller/tests/transaction.rs
index 22731c0d..6c79e1f5 100644
--- a/controller/tests/transaction.rs
+++ b/controller/tests/transaction.rs
@@ -119,13 +119,9 @@ fn basic_transaction_api(test_dir: &'static str) -> Result<(), libwallet::Error>
 
 		// Check we have a single kernel and that it is a Plain kernel (no lock_height).
 		assert_eq!(slate.tx.kernels().len(), 1);
-		assert_eq!(
-			slate.tx.kernels().first().map(|k| k.lock_height).unwrap(),
-			0
-		);
 		assert_eq!(
 			slate.tx.kernels().first().map(|k| k.features).unwrap(),
-			transaction::KernelFeatures::Plain
+			transaction::KernelFeatures::Plain { fee: 0 }
 		);
 
 		Ok(())
diff --git a/libwallet/src/slate.rs b/libwallet/src/slate.rs
index 310e0539..a3ddd92b 100644
--- a/libwallet/src/slate.rs
+++ b/libwallet/src/slate.rs
@@ -20,8 +20,7 @@ use crate::error::{Error, ErrorKind};
 use crate::grin_core::core::amount_to_hr_string;
 use crate::grin_core::core::committed::Committed;
 use crate::grin_core::core::transaction::{
-	kernel_features, kernel_sig_msg, Input, Output, Transaction, TransactionBody, TxKernel,
-	Weighting,
+	Input, KernelFeatures, Output, Transaction, TransactionBody, TxKernel, Weighting,
 };
 use crate::grin_core::core::verifier_cache::LruVerifierCache;
 use crate::grin_core::libtx::{aggsig, build, proof::ProofBuild, secp_ser, tx_fee};
@@ -290,11 +289,16 @@ impl Slate {
 	}
 
 	// This is the msg that we will sign as part of the tx kernel.
-	// Currently includes the fee and the lock_height.
+	// If lock_height is 0 then build a plain kernel, otherwise build a height locked kernel.
 	fn msg_to_sign(&self) -> Result<secp::Message, Error> {
-		// Currently we only support interactively creating a tx with a "default" kernel.
-		let features = kernel_features(self.lock_height);
-		let msg = kernel_sig_msg(self.fee, self.lock_height, features)?;
+		let features = match self.lock_height {
+			0 => KernelFeatures::Plain { fee: self.fee },
+			_ => KernelFeatures::HeightLocked {
+				fee: self.fee,
+				lock_height: self.lock_height,
+			},
+		};
+		let msg = features.kernel_sig_msg()?;
 		Ok(msg)
 	}
 
@@ -881,19 +885,19 @@ impl From<&Output> for OutputV2 {
 
 impl From<&TxKernel> for TxKernelV2 {
 	fn from(kernel: &TxKernel) -> TxKernelV2 {
-		let TxKernel {
-			features,
-			fee,
-			lock_height,
-			excess,
-			excess_sig,
-		} = *kernel;
+		let (features, fee, lock_height) = match kernel.features {
+			KernelFeatures::Plain { fee } => (CompatKernelFeatures::Plain, fee, 0),
+			KernelFeatures::Coinbase => (CompatKernelFeatures::Coinbase, 0, 0),
+			KernelFeatures::HeightLocked { fee, lock_height } => {
+				(CompatKernelFeatures::HeightLocked, fee, lock_height)
+			}
+		};
 		TxKernelV2 {
 			features,
 			fee,
 			lock_height,
-			excess,
-			excess_sig,
+			excess: kernel.excess,
+			excess_sig: kernel.excess_sig,
 		}
 	}
 }
@@ -1025,19 +1029,23 @@ impl From<&OutputV2> for Output {
 
 impl From<&TxKernelV2> for TxKernel {
 	fn from(kernel: &TxKernelV2) -> TxKernel {
-		let TxKernelV2 {
-			features,
-			fee,
-			lock_height,
-			excess,
-			excess_sig,
-		} = *kernel;
+		let (fee, lock_height) = (kernel.fee, kernel.lock_height);
+		let features = match kernel.features {
+			CompatKernelFeatures::Plain => KernelFeatures::Plain { fee },
+			CompatKernelFeatures::Coinbase => KernelFeatures::Coinbase,
+			CompatKernelFeatures::HeightLocked => KernelFeatures::HeightLocked { fee, lock_height },
+		};
 		TxKernel {
 			features,
-			fee,
-			lock_height,
-			excess,
-			excess_sig,
+			excess: kernel.excess,
+			excess_sig: kernel.excess_sig,
 		}
 	}
 }
+
+#[derive(Clone, Copy, Debug, Serialize, Deserialize)]
+pub enum CompatKernelFeatures {
+	Plain,
+	Coinbase,
+	HeightLocked,
+}
diff --git a/libwallet/src/slate_versions/v2.rs b/libwallet/src/slate_versions/v2.rs
index 336fb896..2c5832f8 100644
--- a/libwallet/src/slate_versions/v2.rs
+++ b/libwallet/src/slate_versions/v2.rs
@@ -35,13 +35,14 @@
 //!    orig_version: u16,
 //!    block_header_version: u16,
 
-use crate::grin_core::core::transaction::{KernelFeatures, OutputFeatures};
+use crate::grin_core::core::transaction::OutputFeatures;
 use crate::grin_core::libtx::secp_ser;
 use crate::grin_keychain::BlindingFactor;
 use crate::grin_util::secp;
 use crate::grin_util::secp::key::PublicKey;
 use crate::grin_util::secp::pedersen::{Commitment, RangeProof};
 use crate::grin_util::secp::Signature;
+use crate::slate::CompatKernelFeatures;
 use uuid::Uuid;
 
 #[derive(Serialize, Deserialize, Debug, Clone)]
@@ -162,7 +163,7 @@ pub struct OutputV2 {
 #[derive(Serialize, Deserialize, Debug, Clone)]
 pub struct TxKernelV2 {
 	/// Options for a kernel's structure or use
-	pub features: KernelFeatures,
+	pub features: CompatKernelFeatures,
 	/// Fee originally included in the transaction this proof is for.
 	#[serde(with = "secp_ser::string_or_u64")]
 	pub fee: u64,
diff --git a/libwallet/tests/libwallet.rs b/libwallet/tests/libwallet.rs
index 09505794..e858052b 100644
--- a/libwallet/tests/libwallet.rs
+++ b/libwallet/tests/libwallet.rs
@@ -23,7 +23,9 @@ use grin_wallet_util::grin_util::secp::key::{PublicKey, SecretKey};
 use rand::thread_rng;
 
 fn kernel_sig_msg() -> secp::Message {
-	transaction::kernel_sig_msg(0, 0, transaction::KernelFeatures::Plain).unwrap()
+	transaction::KernelFeatures::Plain { fee: 0 }
+		.kernel_sig_msg()
+		.unwrap()
 }
 
 #[test]