diff --git a/libguh/devicemanager.cpp b/libguh/devicemanager.cpp
index 8a6fa391..e9ed8904 100644
--- a/libguh/devicemanager.cpp
+++ b/libguh/devicemanager.cpp
@@ -171,13 +171,30 @@ DeviceManager::DeviceError DeviceManager::addConfiguredDeviceInternal(const Devi
         qWarning() << "cannot find a device class with id" << deviceClassId;
         return DeviceErrorDeviceClassNotFound;
     }
+
+    // Make sure we have all required params
     foreach (const QVariant &param, deviceClass.params()) {
         if (!params.contains(param.toMap().value("name").toString())) {
             qWarning() << "Missing parameter when creating device:" << param.toMap().value("name").toString();
             return DeviceErrorMissingParameter;
         }
-        // TODO: Check if parameter type matches
     }
+    // Make sure we don't have unused params
+    foreach (const QString &paramId, params.keys()) {
+        qDebug() << "searching" << paramId << "in" << deviceClass.params();
+        bool found = false;
+        foreach (const QVariant &param, deviceClass.params()) {
+            if (param.toMap().value("name").toString() == paramId) {
+                found = true;
+                continue;
+            }
+        }
+        if (!found) {
+            // TODO: Check if parameter type matches
+            return DeviceErrorDeviceParameterError;
+        }
+    }
+
     foreach(Device *device, m_configuredDevices) {
         if (device->id() == id) {
             return DeviceErrorDuplicateUuid;
diff --git a/plugins/deviceplugins/openweathermap/devicepluginopenweathermap.cpp b/plugins/deviceplugins/openweathermap/devicepluginopenweathermap.cpp
index dfe1deaf..9ef595ba 100644
--- a/plugins/deviceplugins/openweathermap/devicepluginopenweathermap.cpp
+++ b/plugins/deviceplugins/openweathermap/devicepluginopenweathermap.cpp
@@ -172,12 +172,6 @@ QList<DeviceClass> DevicePluginOpenweathermap::supportedDevices() const
     DeviceClass deviceClassOpenweathermap(pluginId(), openweathermapVendorId, DeviceClassId("985195aa-17ad-4530-88a4-cdd753d747d7"));
     deviceClassOpenweathermap.setName("Weather from openweathermap");
 
-    QVariantList weatherParams;
-    QVariantMap autoDetectParam;
-    autoDetectParam.insert("name", "autodetect");
-    autoDetectParam.insert("type", "bool");
-    weatherParams.append(autoDetectParam);
-
     // Actions
     QList<ActionType> weatherActions;
     ActionType updateWeather(ActionTypeId("cfbc6504-d86f-4856-8dfa-97b6fbb385e4"));
diff --git a/server/jsonrpc/devicehandler.cpp b/server/jsonrpc/devicehandler.cpp
index c324fe8a..66e46b7d 100644
--- a/server/jsonrpc/devicehandler.cpp
+++ b/server/jsonrpc/devicehandler.cpp
@@ -227,6 +227,10 @@ QVariantMap DeviceHandler::AddConfiguredDevice(const QVariantMap &params)
         returns.insert("errorMessage", "Error creating device. This device can't be created this way.");
         returns.insert("success", false);
         break;
+    case DeviceManager::DeviceErrorDeviceParameterError:
+        returns.insert("errorMessage", "Error creating device. Invalid device parameter.");
+        returns.insert("success", false);
+        break;
     default:
         returns.insert("errorMessage", "Unknown error.");
         returns.insert("success", false);
diff --git a/server/jsonrpc/jsonrpcserver.cpp b/server/jsonrpc/jsonrpcserver.cpp
index 5a443253..d2d4bf2e 100644
--- a/server/jsonrpc/jsonrpcserver.cpp
+++ b/server/jsonrpc/jsonrpcserver.cpp
@@ -69,9 +69,11 @@ JsonRPCServer::JsonRPCServer(QObject *parent):
 
     params.clear(); returns.clear();
     setDescription("SetNotificationStatus", "Enable/Disable notifications for this connections.");
+    params.insert("enabled", "bool");
     setParams("SetNotificationStatus", params);
     returns.insert("success", "bool");
     returns.insert("enabled", "bool");
+    returns.insert("errorMessage", "string");
     setReturns("SetNotificationStatus", returns);
 
     // Now set up the logic
diff --git a/server/jsonrpc/jsontypes.cpp b/server/jsonrpc/jsontypes.cpp
index 505b1a80..e6a7ccda 100644
--- a/server/jsonrpc/jsontypes.cpp
+++ b/server/jsonrpc/jsontypes.cpp
@@ -68,7 +68,7 @@ void JsonTypes::init()
     s_stateType.insert("id", "uuid");
     s_stateType.insert("name", "string");
     s_stateType.insert("type", basicTypesRef());
-//    s_stateType.insert("default", "value");
+    s_stateType.insert("defaultValue", "variant");
 
     // State
     s_state.insert("stateTypeId", "uuid");
@@ -278,10 +278,11 @@ QVariantMap JsonTypes::packRule(const Rule &rule)
 QPair<bool, QString> JsonTypes::validateMap(const QVariantMap &templateMap, const QVariantMap &map)
 {
     s_lastError.clear();
+
+    // Make sure all values defined in the template are around
     foreach (const QString &key, templateMap.keys()) {
         QString strippedKey = key;
         strippedKey.remove(QRegExp("^o:"));
-
         if (!key.startsWith("o:") && !map.contains(strippedKey)) {
             qDebug() << "*** missing key" << key;
             qDebug() << "Expected:" << templateMap;
@@ -297,6 +298,18 @@ QPair<bool, QString> JsonTypes::validateMap(const QVariantMap &templateMap, cons
             }
         }
     }
+
+    // Make sure there aren't any other parameters than the allowed ones
+    foreach (const QString &key, map.keys()) {
+        QString optKey = "o:" + key;
+
+        if (!templateMap.contains(key) && !templateMap.contains(optKey)) {
+            qDebug() << "Forbidden param" << key << "in params";
+            QJsonDocument jsonDoc = QJsonDocument::fromVariant(map);
+            return report(false, QString("Forbidden key \"%1\" in %2").arg(key).arg(QString(jsonDoc.toJson())));
+        }
+    }
+
     return report(true, "");
 }
 
@@ -331,6 +344,7 @@ QPair<bool, QString> JsonTypes::validateList(const QVariantList &templateList, c
 
     for (int i = 0; i < list.count(); ++i) {
         QVariant listEntry = list.at(i);
+        qDebug() << "validating" << list << templateList;
         QPair<bool, QString> result = validateVariant(entryTemplate, listEntry);
         if (!result.first) {
             qDebug() << "List entry not matching template";