diff --git a/errors/common.go b/errors/common.go
index 43d722c8ad..d38f6b07b6 100644
--- a/errors/common.go
+++ b/errors/common.go
@@ -3,10 +3,10 @@ package errors
 
 import (
 	"fmt"
+	"reflect"
 
 	"github.com/pkg/errors"
 	abci "github.com/tendermint/abci/types"
-	"github.com/tendermint/basecoin"
 )
 
 var (
@@ -23,8 +23,21 @@ var (
 	errUnknownModule     = fmt.Errorf("Unknown module")
 )
 
-func ErrUnknownTxType(tx basecoin.Tx) TMError {
-	msg := fmt.Sprintf("%T", tx.Unwrap())
+// some crazy reflection to unwrap any generated struct.
+func unwrap(i interface{}) interface{} {
+	v := reflect.ValueOf(i)
+	m := v.MethodByName("Unwrap")
+	if m.IsValid() {
+		out := m.Call(nil)
+		if len(out) == 1 {
+			return out[0].Interface()
+		}
+	}
+	return i
+}
+
+func ErrUnknownTxType(tx interface{}) TMError {
+	msg := fmt.Sprintf("%T", unwrap(tx))
 	w := errors.Wrap(errUnknownTxType, msg)
 	return WithCode(w, abci.CodeType_UnknownRequest)
 }
@@ -32,8 +45,8 @@ func IsUnknownTxTypeErr(err error) bool {
 	return IsSameError(errUnknownTxType, err)
 }
 
-func ErrInvalidFormat(tx basecoin.Tx) TMError {
-	msg := fmt.Sprintf("%T", tx.Unwrap())
+func ErrInvalidFormat(tx interface{}) TMError {
+	msg := fmt.Sprintf("%T", unwrap(tx))
 	w := errors.Wrap(errInvalidFormat, msg)
 	return WithCode(w, abci.CodeType_UnknownRequest)
 }
diff --git a/errors/common_test.go b/errors/common_test.go
index e863ac786a..42e3204a5e 100644
--- a/errors/common_test.go
+++ b/errors/common_test.go
@@ -5,15 +5,26 @@ import (
 	"testing"
 
 	"github.com/stretchr/testify/assert"
-	"github.com/tendermint/basecoin"
 )
 
+type validate interface {
+	ValidateBasic() error
+}
+
+type holder struct {
+	validate
+}
+
+func (h holder) Unwrap() validate {
+	return h.validate
+}
+
 type DemoTx struct {
 	Age int
 }
 
-func (t DemoTx) Wrap() basecoin.Tx {
-	return basecoin.Tx{t}
+func (t DemoTx) Wrap() holder {
+	return holder{t}
 }
 
 func (t DemoTx) ValidateBasic() error {
@@ -32,7 +43,8 @@ func TestErrorMatches(t *testing.T) {
 		{errMissingSignature, ErrUnauthorized(), false},
 		{errMissingSignature, ErrMissingSignature(), true},
 		{errWrongChain, ErrWrongChain("hakz"), true},
-		{errUnknownTxType, ErrUnknownTxType(basecoin.Tx{}), true},
+		{errUnknownTxType, ErrUnknownTxType(holder{}), true},
+		{errUnknownTxType, ErrUnknownTxType("some text here..."), true},
 		{errUnknownTxType, ErrUnknownTxType(DemoTx{5}.Wrap()), true},
 	}
 
diff --git a/tx.go b/tx.go
index 2e8d5f2bd8..cc143ffc43 100644
--- a/tx.go
+++ b/tx.go
@@ -1,8 +1,9 @@
 package basecoin
 
 import (
-	"github.com/pkg/errors"
 	"github.com/tendermint/go-wire/data"
+
+	"github.com/tendermint/basecoin/errors"
 )
 
 const maxTxSize = 10240
@@ -23,12 +24,9 @@ type TxInner interface {
 }
 
 // LoadTx parses a tx from data
-//
-// TODO: label both errors with abci.CodeType_EncodingError
-// need to move errors to avoid import cycle
 func LoadTx(bin []byte) (tx Tx, err error) {
 	if len(bin) > maxTxSize {
-		return tx, errors.New("Tx size exceeds maximum")
+		return tx, errors.ErrTooLarge()
 	}
 
 	// Decode tx