diff --git a/src/add-ons/kernel/network/protocols/unix/UnixFifo.cpp b/src/add-ons/kernel/network/protocols/unix/UnixFifo.cpp
index b8d07b0e54..3d01e50cdf 100644
--- a/src/add-ons/kernel/network/protocols/unix/UnixFifo.cpp
+++ b/src/add-ons/kernel/network/protocols/unix/UnixFifo.cpp
@@ -338,21 +338,20 @@ UnixFifo::UnixFifo(size_t capacity)
 {
 	fReadCondition.Init(this, "unix fifo read");
 	fWriteCondition.Init(this, "unix fifo write");
-	fLock.sem = -1;
+	mutex_init(&fLock, "unix fifo");
 }
 
 
 UnixFifo::~UnixFifo()
 {
-	if (fLock.sem >= 0)
-		benaphore_destroy(&fLock);
+	mutex_destroy(&fLock);
 }
 
 
 status_t
 UnixFifo::Init()
 {
-	return benaphore_init(&fLock, "unix fifo");
+	return B_OK;
 }
 
 
@@ -498,9 +497,9 @@ UnixFifo::_Read(Request& request, size_t numBytes, bigtime_t timeout,
 		ConditionVariableEntry entry;
 		fReadCondition.Add(&entry, B_CAN_INTERRUPT);
 
-		benaphore_unlock(&fLock);
+		mutex_unlock(&fLock);
 		status_t error = entry.Wait(B_ABSOLUTE_TIMEOUT, timeout);
-		benaphore_lock(&fLock);
+		mutex_lock(&fLock);
 
 		if (error != B_OK)
 			RETURN_ERROR(error);
@@ -526,9 +525,9 @@ UnixFifo::_Read(Request& request, size_t numBytes, bigtime_t timeout,
 		ConditionVariableEntry entry;
 		fReadCondition.Add(&entry, B_CAN_INTERRUPT);
 
-		benaphore_unlock(&fLock);
+		mutex_unlock(&fLock);
 		status_t error = entry.Wait(B_ABSOLUTE_TIMEOUT, timeout);
-		benaphore_lock(&fLock);
+		mutex_lock(&fLock);
 
 		if (error != B_OK)
 			RETURN_ERROR(error);
@@ -558,9 +557,9 @@ UnixFifo::_Write(Request& request, net_buffer* buffer, bigtime_t timeout,
 		ConditionVariableEntry entry;
 		fWriteCondition.Add(&entry, B_CAN_INTERRUPT);
 
-		benaphore_unlock(&fLock);
+		mutex_unlock(&fLock);
 		status_t error = entry.Wait(B_ABSOLUTE_TIMEOUT, timeout);
-		benaphore_lock(&fLock);
+		mutex_lock(&fLock);
 
 		if (error != B_OK)
 			RETURN_ERROR(error);
@@ -585,9 +584,9 @@ UnixFifo::_Write(Request& request, net_buffer* buffer, bigtime_t timeout,
 			ConditionVariableEntry entry;
 			fWriteCondition.Add(&entry, B_CAN_INTERRUPT);
 	
-			benaphore_unlock(&fLock);
+			mutex_unlock(&fLock);
 			error = entry.Wait(B_ABSOLUTE_TIMEOUT, timeout);
-			benaphore_lock(&fLock);
+			mutex_lock(&fLock);
 
 			if (error != B_OK)
 				RETURN_ERROR(error);
diff --git a/src/add-ons/kernel/network/protocols/unix/UnixFifo.h b/src/add-ons/kernel/network/protocols/unix/UnixFifo.h
index 1752fbc1cf..879cf58e33 100644
--- a/src/add-ons/kernel/network/protocols/unix/UnixFifo.h
+++ b/src/add-ons/kernel/network/protocols/unix/UnixFifo.h
@@ -74,12 +74,12 @@ public:
 
 	bool Lock()
 	{
-		return benaphore_lock(&fLock) == B_OK;
+		return mutex_lock(&fLock) == B_OK;
 	}
 
 	void Unlock()
 	{
-		benaphore_unlock(&fLock);
+		mutex_unlock(&fLock);
 	}
 
 	void Shutdown(uint32 shutdown);
@@ -124,7 +124,7 @@ private:
 		size_t& bytesWritten);
 
 private:
-	benaphore			fLock;
+	mutex				fLock;
 	UnixBufferQueue		fBuffer;
 	RequestList			fReaders;
 	RequestList			fWriters;