diff --git a/kotlinx-coroutines-core/src/main/kotlin/kotlinx/coroutines/experimental/intrinsics/Undispatched.kt b/kotlinx-coroutines-core/src/main/kotlin/kotlinx/coroutines/experimental/intrinsics/Undispatched.kt
index 43419fb..e5b18c0 100644
--- a/kotlinx-coroutines-core/src/main/kotlin/kotlinx/coroutines/experimental/intrinsics/Undispatched.kt
+++ b/kotlinx-coroutines-core/src/main/kotlin/kotlinx/coroutines/experimental/intrinsics/Undispatched.kt
@@ -17,7 +17,7 @@
 package kotlinx.coroutines.experimental.intrinsics
 
 import kotlin.coroutines.experimental.Continuation
-import kotlin.coroutines.experimental.intrinsics.COROUTINE_SUSPENDED
+import kotlin.coroutines.experimental.intrinsics.*
 import kotlin.coroutines.experimental.suspendCoroutine
 
 /**
@@ -26,9 +26,9 @@
  * @suppress **This is unstable API and it is subject to change.**
  */
 @Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN", "UNCHECKED_CAST")
-internal fun <R> (suspend () -> R).startUndispatchedCoroutine(completion: Continuation<R>) {
+internal fun <R> (suspend () -> R).startCoroutineUndispatched(completion: Continuation<R>) {
     val value = try {
-        (this as kotlin.jvm.functions.Function1<Continuation<R>, Any?>).invoke(completion)
+        startCoroutineUninterceptedOrReturn(completion)
     } catch (e: Throwable) {
         completion.resumeWithException(e)
         return
@@ -43,9 +43,9 @@
  * @suppress **This is unstable API and it is subject to change.**
  */
 @Suppress("PLATFORM_CLASS_MAPPED_TO_KOTLIN", "UNCHECKED_CAST")
-internal fun <E, R> (suspend (E) -> R).startUndispatchedCoroutine(element: E, completion: Continuation<R>) {
+internal fun <E, R> (suspend (E) -> R).startCoroutineUndispatched(element: E, completion: Continuation<R>) {
     val value = try {
-        (this as kotlin.jvm.functions.Function2<E, Continuation<R>, Any?>).invoke(element, completion)
+        startCoroutineUninterceptedOrReturn(element, completion)
     } catch (e: Throwable) {
         completion.resumeWithException(e)
         return