diff --git a/ghc/rts/Capability.c b/ghc/rts/Capability.c
index 2dec782fd90f269b34c31af41f6c73a08fddedf3..638dd4ad7e9c76c591a41f250a03042187a09cda 100644
--- a/ghc/rts/Capability.c
+++ b/ghc/rts/Capability.c
@@ -68,8 +68,8 @@ Condition thread_ready_cond = INIT_COND_VAR;
  * the number of tasks currently blocked waiting on thread_ready_cond.
  * (if > 0 => no need for a new task, just unblock an existing one).
  *
- * waitForWork() takes care of keeping it up-to-date; Task.startTask()
- * uses its current value.
+ * waitForWorkCapability() takes care of keeping it up-to-date;
+ * Task.startTask() uses its current value.
  */
 nat rts_n_waiting_tasks = 0;
 #endif
diff --git a/ghc/rts/Capability.h b/ghc/rts/Capability.h
index 71359b60aaa1c610699acde3d5ceae5d4f6fff7c..8a3260ce2d01de17c4f04349fbea25baaf2f74f7 100644
--- a/ghc/rts/Capability.h
+++ b/ghc/rts/Capability.h
@@ -32,10 +32,14 @@ extern void initCapabilities(void);
 extern void grabCapability(Capability** pCap);
 extern void releaseCapability(Capability* cap);
 
-#if defined(RTS_SUPPORTS_THREADS)
-/* total number of available capabilities */
 extern nat rts_n_free_capabilities;  
-extern nat rts_n_waiting_workers;
+#if defined(RTS_SUPPORTS_THREADS)
+/* number of worker threads waiting to do good work within
+   the RTS. Used by Task.c (only) to determine whether or not
+   new worker threads needs to be created (when an external call
+   is made).
+ */
+extern nat rts_n_waiting_workers; /* used by Task.c to determine */
 
 extern void grabReturnCapability(Mutex* pMutex, Capability** pCap);
 extern void yieldToReturningWorker(Mutex* pMutex, Capability* cap);