diff --git a/archive/v0.1.20/mithril-tests.js b/archive/v0.1.20/mithril-tests.js
index 15612a4b..07324e42 100644
--- a/archive/v0.1.20/mithril-tests.js
+++ b/archive/v0.1.20/mithril-tests.js
@@ -361,33 +361,31 @@ Mithril = m = new function app(window, undefined) {
 		return value
 	}
 
-	m.prop = function(store) {
-		function isPromise(obj) {
-			return typeof store === 'object' && typeof store.then === 'function'
-		}
-
+	function _prop(store) {
 		var prop = function() {
-			if (arguments.length) {
-				store = arguments[0]
-				if (isPromise(store)) {
-					store.then(prop)
-				}
-			}
-
-			return isPromise(store) ? undefined : store
+			if (arguments.length) store = arguments[0]
+			return store
 		}
 
 		prop.toJSON = function() {
-			return isPromise(store) ? undefined : store
-		}
-
-		if (isPromise(store)) {
-			store.then(prop)
+			return store
 		}
 
 		return prop
 	}
 
+	m.prop = function (store) {
+		if ((typeof store === 'object' || typeof store === 'function') &&
+				typeof store.then === 'function') {
+			var prop = _prop()
+			newPromisedProp(prop, store).then(prop)
+
+			return prop
+		}
+
+		return _prop(store)
+	}
+
 	var roots = [], modules = [], controllers = [], lastRedrawId = 0, computePostRedrawHook = null, prevented = false
 	m.module = function(root, module) {
 		var index = roots.indexOf(root)
@@ -566,6 +564,25 @@ Mithril = m = new function app(window, undefined) {
 	}
 
 	var none = {}
+	function newPromisedProp(prop, promise) {
+		prop.then = function () {
+			var newProp = m.prop()
+			return newPromisedProp(newProp,
+				promise.then.apply(promise, arguments).then(newProp))
+		}
+		prop.promise = prop
+		prop.resolve = function (val) {
+			prop(val)
+			promise = promise.resolve.apply(promise, arguments)
+			return prop
+		}
+		prop.reject = function () {
+			promise = promise.reject.apply(promise, arguments)
+			return prop
+		}
+
+		return prop
+	}
 	m.deferred = function () {
 
 		// Promiz.mithril.js | Zolmeister | MIT
@@ -695,26 +712,6 @@ Mithril = m = new function app(window, undefined) {
 			}
 		}
 
-		function newPromisedProp(prop, promise) {
-			prop.then = function () {
-				var newProp = m.prop(prop())
-				return newPromisedProp(newProp,
-					promise.then.apply(promise, arguments).then(newProp))
-			}
-			prop.promise = prop
-			prop.resolve = function (val) {
-				prop(val)
-				promise = promise.resolve.apply(promise, arguments)
-				return prop
-			}
-			prop.reject = function () {
-				promise = promise.reject.apply(promise, arguments)
-				return prop
-			}
-
-			return prop
-		}
-
 		return newPromisedProp(m.prop(), new Deferred())
 	}
 	m.sync = function(args) {
@@ -2414,29 +2411,20 @@ function testMithril(mock) {
 		return JSON.stringify(obj) === '{"prop":"test"}'
 	})
 	test(function() {
-		var prop = m.prop({
-			then: function(cb) {cb("test")}
-		})
+		var defer = m.deferred()
+		var prop = m.prop(defer.promise)
+		defer.resolve("test")
+
 		return prop() === "test"
 	})
 	test(function() {
-		var prop = m.prop({
-			then: function() {}
+		var defer = m.deferred()
+		var prop = m.prop(defer.promise).then(function () {
+			return "test2"
 		})
+		defer.resolve("test")
 
-		return prop() === undefined
-	})
-	test(function() {
-		var promise = {
-			then: function(cb) {this.cb = cb},
-			resolve: function (x) {
-				this.cb(x)
-			}
-		}
-		var prop = m.prop(promise)
-		promise.resolve("test")
-
-		return prop() === "test"
+		return prop() === "test2"
 	})
 
 	//m.request
diff --git a/mithril.js b/mithril.js
index 077bcdea..e1a10c34 100644
--- a/mithril.js
+++ b/mithril.js
@@ -361,33 +361,31 @@ Mithril = m = new function app(window, undefined) {
 		return value
 	}
 
-	m.prop = function(store) {
-		function isPromise(obj) {
-			return typeof store === 'object' && typeof store.then === 'function'
-		}
-
+	function _prop(store) {
 		var prop = function() {
-			if (arguments.length) {
-				store = arguments[0]
-				if (isPromise(store)) {
-					store.then(prop)
-				}
-			}
-
-			return isPromise(store) ? undefined : store
+			if (arguments.length) store = arguments[0]
+			return store
 		}
 
 		prop.toJSON = function() {
-			return isPromise(store) ? undefined : store
-		}
-
-		if (isPromise(store)) {
-			store.then(prop)
+			return store
 		}
 
 		return prop
 	}
 
+	m.prop = function (store) {
+		if ((typeof store === 'object' || typeof store === 'function') &&
+				typeof store.then === 'function') {
+			var prop = _prop()
+			newPromisedProp(prop, store).then(prop)
+
+			return prop
+		}
+
+		return _prop(store)
+	}
+
 	var roots = [], modules = [], controllers = [], lastRedrawId = 0, computePostRedrawHook = null, prevented = false
 	m.module = function(root, module) {
 		var index = roots.indexOf(root)
@@ -566,6 +564,25 @@ Mithril = m = new function app(window, undefined) {
 	}
 
 	var none = {}
+	function newPromisedProp(prop, promise) {
+		prop.then = function () {
+			var newProp = m.prop()
+			return newPromisedProp(newProp,
+				promise.then.apply(promise, arguments).then(newProp))
+		}
+		prop.promise = prop
+		prop.resolve = function (val) {
+			prop(val)
+			promise = promise.resolve.apply(promise, arguments)
+			return prop
+		}
+		prop.reject = function () {
+			promise = promise.reject.apply(promise, arguments)
+			return prop
+		}
+
+		return prop
+	}
 	m.deferred = function () {
 
 		// Promiz.mithril.js | Zolmeister | MIT
@@ -695,26 +712,6 @@ Mithril = m = new function app(window, undefined) {
 			}
 		}
 
-		function newPromisedProp(prop, promise) {
-			prop.then = function () {
-				var newProp = m.prop(prop())
-				return newPromisedProp(newProp,
-					promise.then.apply(promise, arguments).then(newProp))
-			}
-			prop.promise = prop
-			prop.resolve = function (val) {
-				prop(val)
-				promise = promise.resolve.apply(promise, arguments)
-				return prop
-			}
-			prop.reject = function () {
-				promise = promise.reject.apply(promise, arguments)
-				return prop
-			}
-
-			return prop
-		}
-
 		return newPromisedProp(m.prop(), new Deferred())
 	}
 	m.sync = function(args) {
diff --git a/tests/mithril-tests.js b/tests/mithril-tests.js
index f053a9b6..a009ee72 100644
--- a/tests/mithril-tests.js
+++ b/tests/mithril-tests.js
@@ -1414,29 +1414,20 @@ function testMithril(mock) {
 		return JSON.stringify(obj) === '{"prop":"test"}'
 	})
 	test(function() {
-		var prop = m.prop({
-			then: function(cb) {cb("test")}
-		})
+		var defer = m.deferred()
+		var prop = m.prop(defer.promise)
+		defer.resolve("test")
+
 		return prop() === "test"
 	})
 	test(function() {
-		var prop = m.prop({
-			then: function() {}
+		var defer = m.deferred()
+		var prop = m.prop(defer.promise).then(function () {
+			return "test2"
 		})
+		defer.resolve("test")
 
-		return prop() === undefined
-	})
-	test(function() {
-		var promise = {
-			then: function(cb) {this.cb = cb},
-			resolve: function (x) {
-				this.cb(x)
-			}
-		}
-		var prop = m.prop(promise)
-		promise.resolve("test")
-
-		return prop() === "test"
+		return prop() === "test2"
 	})
 
 	//m.request