diff --git a/jsonapi.go b/jsonapi.go
index 271bae90..af347d90 100644
--- a/jsonapi.go
+++ b/jsonapi.go
@@ -273,8 +273,7 @@ func CreateMessageWithId(message string, id interface{}, args ...interface{}) ([
 		}
 		finalMessage, err = jsonWithArgs(message, id, args)
 	// Two required strings
-	case "setaccount", "signmessage", "walletpassphrase",
-		"walletpassphrasechange":
+	case "setaccount", "signmessage", "walletpassphrasechange":
 		if len(args) != 2 {
 			err = fmt.Errorf("Missing arguments for %s", message)
 			return finalMessage, err
@@ -286,6 +285,19 @@ func CreateMessageWithId(message string, id interface{}, args ...interface{}) ([
 			return finalMessage, err
 		}
 		finalMessage, err = jsonWithArgs(message, id, args)
+	// One required string, one required int
+	case "walletpassphrase":
+		if len(args) != 2 {
+			err = fmt.Errorf("Missing arguments for %s", message)
+			return finalMessage, err
+		}
+		_, ok1 := args[0].(string)
+		_, ok2 := args[1].(int)
+		if !ok1 || !ok2 {
+			err = fmt.Errorf("Arguments must be string and int for %s", message)
+			return finalMessage, err
+		}
+		finalMessage, err = jsonWithArgs(message, id, args)
 	// Three required strings
 	case "verifymessage":
 		if len(args) != 3 {
diff --git a/jsonapi_test.go b/jsonapi_test.go
index 108b032c..e243d2dd 100644
--- a/jsonapi_test.go
+++ b/jsonapi_test.go
@@ -168,6 +168,9 @@ var cmdtests = []struct {
 	{"listsinceblock", []interface{}{"test"}, true},
 	{"listsinceblock", []interface{}{}, true},
 	{"listsinceblock", []interface{}{1, "test"}, false},
+	{"walletpassphrase", []interface{}{"test", 1}, true},
+	{"walletpassphrase", []interface{}{"test"}, false},
+	{"walletpassphrase", []interface{}{"test", "test"}, false},
 	{"fakecommand", nil, false},
 }
 
diff --git a/test_coverage.txt b/test_coverage.txt
index 2b77f721..34190458 100644
--- a/test_coverage.txt
+++ b/test_coverage.txt
@@ -1,5 +1,5 @@
 
-github.com/conformal/btcjson/jsonapi.go	 CreateMessageWithId	 100.00% (323/323)
+github.com/conformal/btcjson/jsonapi.go	 CreateMessageWithId	 100.00% (332/332)
 github.com/conformal/btcjson/jsonapi.go	 ReadResultCmd		 100.00% (63/63)
 github.com/conformal/btcjson/jsonapi.go	 JSONToAmount		 100.00% (15/15)
 github.com/conformal/btcjson/jsonapi.go	 JSONGetMethod		 100.00% (14/14)
@@ -11,5 +11,5 @@ github.com/conformal/btcjson/jsonapi.go	 IsValidIdType		 100.00% (3/3)
 github.com/conformal/btcjson/jsonapi.go	 CreateMessage		 100.00% (2/2)
 github.com/conformal/btcjson/jsonapi.go	 RpcCommand		 61.54% (8/13)
 github.com/conformal/btcjson/jsonapi.go	 RpcRawCommand		 53.33% (8/15)
-github.com/conformal/btcjson		 -------------------	 97.46% (461/473)
+github.com/conformal/btcjson		 -------------------	 97.51% (470/482)