diff --git a/rtl/os2/tthread.inc b/rtl/os2/tthread.inc
index bde5735d0e..b5596c9354 100644
--- a/rtl/os2/tthread.inc
+++ b/rtl/os2/tthread.inc
@@ -17,11 +17,11 @@
 (* OS/2 specific declarations - see unit DosCalls for descriptions *)
 
 type
- TByteArray = array [0..$fff0] of byte;
+{ TByteArray = array [0..$fff0] of byte;
  PByteArray = ^TByteArray;
-
- TThreadEntry = function (Param: pointer): longint; cdecl;
-
+}
+{ TThreadEntry = function (Param: pointer): longint; cdecl;
+}
  TSysThreadIB = record
                  TID, Priority, Version: longint;
                  MCCount, MCForceFlag: word;
@@ -46,9 +46,9 @@ type
 
 
 const
- deThread = 0;
+{ deThread = 0;
  deProcess = 1;
-
+}
  dtSuspended = 1;
  dtStack_Commited = 2;
 
@@ -61,7 +61,7 @@ procedure DosGetInfoBlocks (PATIB: PPThreadInfoBlock;
 
 function DosSetPriority (Scope, TrClass: cardinal; Delta: longint;
              PortID: cardinal): cardinal; cdecl; external 'DOSCALLS' index 236;
-
+{
 procedure DosExit (Action, Result: cardinal); cdecl;
                                                  external 'DOSCALLS' index 233;
 
@@ -77,7 +77,7 @@ function DosResumeThread (TID: cardinal): cardinal; cdecl;
 
 function DosSuspendThread (TID: cardinal): cardinal; cdecl;
                                                  external 'DOSCALLS' index 238;
-
+}
 function DosWaitThread (var TID: cardinal; Option: cardinal): cardinal; cdecl;
                                                  external 'DOSCALLS' index 349;
 
@@ -89,15 +89,46 @@ const
 
 (* Implementation of exported functions *)
 
-procedure AddThread (T: TThread);
+procedure AddThread;
 begin
- Inc (ThreadCount);
+ InterlockedIncrement (ThreadCount);
 end;
 
 
-procedure RemoveThread (T: TThread);
+procedure RemoveThread;
 begin
- Dec (ThreadCount);
+ InterlockedDecrement (ThreadCount);
+end;
+
+
+constructor TThread.Create(CreateSuspended: Boolean;
+                           const StackSize: SizeUInt = DefaultStackSize);
+var
+  Flags: cardinal;
+begin
+  inherited Create;
+  AddThread;
+  Flags := dtStack_Commited;
+  FSuspended := CreateSuspended;
+  if FSuspended then Flags := Flags or dtSuspended;
+  FHandle := BeginThread (nil, StackSize, @ThreadProc, pointer (Self),
+                                                             Flags, FThreadID);
+  FFatalException := nil;
+end;
+
+
+destructor TThread.Destroy;
+begin
+ if not FFinished and not Suspended then
+ begin
+  Terminate;
+  WaitFor;
+ end;
+{ if FHandle <> 0 then DosKillThread (cardinal (FHandle));}
+ FFatalException.Free;
+ FFatalException := nil;
+ inherited Destroy;
+ RemoveThread;
 end;
 
 
@@ -107,6 +138,13 @@ begin
 end;
 
 
+procedure TThread.DoTerminate;
+begin
+ if Assigned (FOnTerminate) then
+   Synchronize (@CallOnTerminate);
+end;
+
+
 function TThread.GetPriority: TThreadPriority;
 var
  PTIB: PThreadInfoBlock;
@@ -142,63 +180,29 @@ end;
 
 procedure TThread.SetSuspended(Value: Boolean);
 begin
- if Value <> FSuspended then
- begin
-  if Value then Suspend else Resume;
- end;
-end;
-
-
-procedure TThread.DoTerminate;
-begin
- if Assigned (FOnTerminate) then Synchronize (@CallOnTerminate);
-end;
-
-
-constructor TThread.Create(CreateSuspended: Boolean;
-                           const StackSize: SizeUInt = DefaultStackSize);
-var
-  Flags: cardinal;
-begin
-  inherited Create;
-  AddThread (Self);
-  FSuspended := CreateSuspended;
-  Flags := dtStack_Commited;
-  if FSuspended then Flags := Flags or dtSuspended;
-  if DosCreateThread (cardinal (FThreadID), @ThreadProc, pointer (Self),
-                                                        Flags, 16384) <> 0 then
-  begin
-   FFinished := true;
-   Destroy;
-  end else FHandle := FThreadID;
-  IsMultiThread := true;
-  FFatalException := nil;
-end;
-
-
-destructor TThread.Destroy;
-begin
- if not FFinished and not Suspended then
- begin
-  Terminate;
-  WaitFor;
- end;
- if FHandle <> -1 then DosKillThread (cardinal (FHandle));
- FFatalException.Free;
- FFatalException := nil;
- inherited Destroy;
- RemoveThread (Self);
-end;
-
-procedure TThread.Resume;
-begin
- FSuspended := not (DosResumeThread (cardinal (FHandle)) = 0);
+  if Value <> FSuspended then
+   begin
+    if Value then
+      Suspend
+    else
+      Resume;
+   end;
 end;
 
 
 procedure TThread.Suspend;
 begin
- FSuspended := DosSuspendThread (cardinal (FHandle)) = 0;
+ FSuspended := true;
+ SuspendThread (FHandle);
+{DosSuspendThread (cardinal (FHandle)) = 0;}
+end;
+
+
+procedure TThread.Resume;
+begin
+  if ResumeThread (FHandle) = 1 then
+    FSuspended := false;
+{ FSuspended := not (DosResumeThread (cardinal (FHandle)) = 0);}
 end;
 
 
@@ -217,5 +221,3 @@ begin
    CheckSynchronize (1000);
  WaitFor := DosWaitThread (FH, dtWait);
 end;
-
-