diff --git a/rx.async.d.ts b/rx.async.d.ts
index fd85bcd7d..783f31d52 100644
--- a/rx.async.d.ts
+++ b/rx.async.d.ts
@@ -10,31 +10,31 @@ declare module Rx {
     interface ObservableStatic {
 		start<T>(func: () => T, context?: any, scheduler?: IScheduler): Observable<T>;
 
-        toAsync<TResult>(func: () => TResult, scheduler?: IScheduler, context?: any): () => Observable<TResult>;
-		toAsync<T1, TResult>(func: (arg1: T1) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1) => Observable<TResult>;
-		toAsync<T1, TResult>(func: (arg1?: T1) => TResult, scheduler?: IScheduler, context?: any): (arg1?: T1) => Observable<TResult>;
-		toAsync<T1, TResult>(func: (...args: T1[]) => TResult, scheduler?: IScheduler, context?: any): (...args: T1[]) => Observable<TResult>;
-		toAsync<T1, T2, TResult>(func: (arg1: T1, arg2: T2) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2) => Observable<TResult>;
-		toAsync<T1, T2, TResult>(func: (arg1: T1, arg2?: T2) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2?: T2) => Observable<TResult>;
-		toAsync<T1, T2, TResult>(func: (arg1?: T1, arg2?: T2) => TResult, scheduler?: IScheduler, context?: any): (arg1?: T1, arg2?: T2) => Observable<TResult>;
-		toAsync<T1, T2, TResult>(func: (arg1: T1, ...args: T2[]) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, ...args: T2[]) => Observable<TResult>;
-		toAsync<T1, T2, TResult>(func: (arg1?: T1, ...args: T2[]) => TResult, scheduler?: IScheduler, context?: any): (arg1?: T1, ...args: T2[]) => Observable<TResult>;
-		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2: T2, arg3: T3) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2, arg3: T3) => Observable<TResult>;
-		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2: T2, arg3?: T3) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2, arg3?: T3) => Observable<TResult>;
-		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2?: T2, arg3?: T3) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2?: T2, arg3?: T3) => Observable<TResult>;
-		toAsync<T1, T2, T3, TResult>(func: (arg1?: T1, arg2?: T2, arg3?: T3) => TResult, scheduler?: IScheduler, context?: any): (arg1?: T1, arg2?: T2, arg3?: T3) => Observable<TResult>;
-		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2: T2, ...args: T3[]) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2, ...args: T3[]) => Observable<TResult>;
-		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2?: T2, ...args: T3[]) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2?: T2, ...args: T3[]) => Observable<TResult>;
-		toAsync<T1, T2, T3, TResult>(func: (arg1?: T1, arg2?: T2, ...args: T3[]) => TResult, scheduler?: IScheduler, context?: any): (arg1?: T1, arg2?: T2, ...args: T3[]) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3: T3, arg4: T4) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2, arg3: T3, arg4: T4) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3: T3, arg4?: T4) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2, arg3: T3, arg4?: T4) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3?: T3, arg4?: T4) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2, arg3?: T3, arg4?: T4) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2?: T2, arg3?: T3, arg4?: T4) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2?: T2, arg3?: T3, arg4?: T4) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1?: T1, arg2?: T2, arg3?: T3, arg4?: T4) => TResult, scheduler?: IScheduler, context?: any): (arg1?: T1, arg2?: T2, arg3?: T3, arg4?: T4) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3: T3, ...args: T4[]) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2, arg3: T3, ...args: T4[]) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3?: T3, ...args: T4[]) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2: T2, arg3?: T3, ...args: T4[]) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2?: T2, arg3?: T3, ...args: T4[]) => TResult, scheduler?: IScheduler, context?: any): (arg1: T1, arg2?: T2, arg3?: T3, ...args: T4[]) => Observable<TResult>;
-		toAsync<T1, T2, T3, T4, TResult>(func: (arg1?: T1, arg2?: T2, arg3?: T3, ...args: T4[]) => TResult, scheduler?: IScheduler, context?: any): (arg1?: T1, arg2?: T2, arg3?: T3, ...args: T4[]) => Observable<TResult>;
+        toAsync<TResult>(func: () => TResult, context?: any, scheduler?: IScheduler): () => Observable<TResult>;
+		toAsync<T1, TResult>(func: (arg1: T1) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1) => Observable<TResult>;
+		toAsync<T1, TResult>(func: (arg1?: T1) => TResult, context?: any, scheduler?: IScheduler): (arg1?: T1) => Observable<TResult>;
+		toAsync<T1, TResult>(func: (...args: T1[]) => TResult, context?: any, scheduler?: IScheduler): (...args: T1[]) => Observable<TResult>;
+		toAsync<T1, T2, TResult>(func: (arg1: T1, arg2: T2) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2) => Observable<TResult>;
+		toAsync<T1, T2, TResult>(func: (arg1: T1, arg2?: T2) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2?: T2) => Observable<TResult>;
+		toAsync<T1, T2, TResult>(func: (arg1?: T1, arg2?: T2) => TResult, context?: any, scheduler?: IScheduler): (arg1?: T1, arg2?: T2) => Observable<TResult>;
+		toAsync<T1, T2, TResult>(func: (arg1: T1, ...args: T2[]) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, ...args: T2[]) => Observable<TResult>;
+		toAsync<T1, T2, TResult>(func: (arg1?: T1, ...args: T2[]) => TResult, context?: any, scheduler?: IScheduler): (arg1?: T1, ...args: T2[]) => Observable<TResult>;
+		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2: T2, arg3: T3) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2, arg3: T3) => Observable<TResult>;
+		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2: T2, arg3?: T3) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2, arg3?: T3) => Observable<TResult>;
+		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2?: T2, arg3?: T3) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2?: T2, arg3?: T3) => Observable<TResult>;
+		toAsync<T1, T2, T3, TResult>(func: (arg1?: T1, arg2?: T2, arg3?: T3) => TResult, context?: any, scheduler?: IScheduler): (arg1?: T1, arg2?: T2, arg3?: T3) => Observable<TResult>;
+		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2: T2, ...args: T3[]) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2, ...args: T3[]) => Observable<TResult>;
+		toAsync<T1, T2, T3, TResult>(func: (arg1: T1, arg2?: T2, ...args: T3[]) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2?: T2, ...args: T3[]) => Observable<TResult>;
+		toAsync<T1, T2, T3, TResult>(func: (arg1?: T1, arg2?: T2, ...args: T3[]) => TResult, context?: any, scheduler?: IScheduler): (arg1?: T1, arg2?: T2, ...args: T3[]) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3: T3, arg4: T4) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2, arg3: T3, arg4: T4) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3: T3, arg4?: T4) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2, arg3: T3, arg4?: T4) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3?: T3, arg4?: T4) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2, arg3?: T3, arg4?: T4) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2?: T2, arg3?: T3, arg4?: T4) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2?: T2, arg3?: T3, arg4?: T4) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1?: T1, arg2?: T2, arg3?: T3, arg4?: T4) => TResult, context?: any, scheduler?: IScheduler): (arg1?: T1, arg2?: T2, arg3?: T3, arg4?: T4) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3: T3, ...args: T4[]) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2, arg3: T3, ...args: T4[]) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2: T2, arg3?: T3, ...args: T4[]) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2: T2, arg3?: T3, ...args: T4[]) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1: T1, arg2?: T2, arg3?: T3, ...args: T4[]) => TResult, context?: any, scheduler?: IScheduler): (arg1: T1, arg2?: T2, arg3?: T3, ...args: T4[]) => Observable<TResult>;
+		toAsync<T1, T2, T3, T4, TResult>(func: (arg1?: T1, arg2?: T2, arg3?: T3, ...args: T4[]) => TResult, context?: any, scheduler?: IScheduler): (arg1?: T1, arg2?: T2, arg3?: T3, ...args: T4[]) => Observable<TResult>;
 	}
 }