diff --git a/components/codetools/examples/fixfilenames.pas b/components/codetools/examples/fixfilenames.pas
index 07fc20c572..62df9e1856 100644
--- a/components/codetools/examples/fixfilenames.pas
+++ b/components/codetools/examples/fixfilenames.pas
@@ -39,6 +39,8 @@ var
   Code: TCodeBuffer;
   Filename: String;
   MissingUnits: TStrings;
+  ReplaceUnits: TStringList;
+  MissingIncludeFilesCodeXYPos: TFPList;
 begin
   // setup the Options
   Options:=TCodeToolsOptions.Create;
@@ -72,8 +74,20 @@ begin
     raise Exception.Create('unable to read '+Filename);
     
   // fix the filenames in the include directives
-  if not CodeToolBoss.FixIncludeFilenames(Code,true) then
+  MissingIncludeFilesCodeXYPos:=nil;
+  if not CodeToolBoss.FixIncludeFilenames(Code,true,
+                                          MissingIncludeFilesCodeXYPos)
+  then
     raise Exception.Create('unable to fix include filesnames in '+Filename+' '+CodeToolBoss.ErrorMessage);
+  CodeToolBoss.FreeListOfPCodeXYPosition(MissingIncludeFilesCodeXYPos);
+
+  // replace some unit names
+  ReplaceUnits:=TStringList.Create;
+  ReplaceUnits.Add('biglettersunit=SysUtils');
+  ReplaceUnits.Free;
+
+  writeln('==================================================================');
+  writeln(Code.Source);
 
   // fix the unitnames in the uses section
   MissingUnits:=nil;
@@ -84,9 +98,12 @@ begin
     writeln('MissingUnits=',MissingUnits.Text);
     if not CodeToolBoss.CommentUnitsInUsesSections(Code,MissingUnits) then
       raise Exception.Create('unable to comment units in uses section in '+Filename+' '+CodeToolBoss.ErrorMessage);
+    MissingUnits.Free;
   end;
-    
+  
   writeln('==================================================================');
   writeln(Code.Source);
+  
+  Options.Free;
 end.
 
diff --git a/components/codetools/examples/scanexamples/brokenfilenames.pas b/components/codetools/examples/scanexamples/brokenfilenames.pas
index 15be199b27..b019003eab 100644
--- a/components/codetools/examples/scanexamples/brokenfilenames.pas
+++ b/components/codetools/examples/scanexamples/brokenfilenames.pas
@@ -10,7 +10,12 @@ uses
   biglettersunit, // must be fixed to BigLettersUnit
   biglettersunit in 'biglettersunit.pas',// -> BigLettersUnit.pas
   biglettersunit in '..\ScanExamples\biglettersunit.pas',// -> ../scanexamples/BigLettersUnit
-  NonExistingUnit1, NonExistingUnit2, SysUtils, NonExistingUnit3;
+  NonExistingUnit1, NonExistingUnit2, SysUtils, NonExistingUnit3,
+  {$IFDEF FPC}
+  NonExistingUnit4
+  {$ELSE}
+  NonExistingUnit5
+  {$ENDIF};
 
 {$I BROKENincfiles.inc}// must be fixed to brokenincfiles.inc
 {$I ../ScanExamples/BROKENincfiles.inc}// must be fixed to ../scanexamples/brokenincfiles.inc
diff --git a/components/codetools/stdcodetools.pas b/components/codetools/stdcodetools.pas
index cc767c0cdc..ca4f49bab4 100644
--- a/components/codetools/stdcodetools.pas
+++ b/components/codetools/stdcodetools.pas
@@ -1000,36 +1000,39 @@ function TStandardCodeTool.CommentUnitsInUsesSections(MissingUnits: TStrings;
   procedure Comment(CommentStartPos, CommentEndPos: integer);
   var
     i: LongInt;
+    CurStartPos: LongInt;
+    CommentNeeded: Boolean;
+    CurEndPos: LongInt;
   begin
     if CommentStartPos>=CommentEndPos then
       RaiseException('TStandardCodeTool Comment');
   
-    // try curly brackets {}
+    // comment with curly brackets {}
     i:=CommentStartPos;
-    while (i<CommentEndPos) and (Src[i]<>'}') do inc(i);
-    if i=CommentEndPos then begin
-      SourceChangeCache.Replace(gtNone,gtNone,CommentStartPos,CommentStartPos,'{');
-      SourceChangeCache.Replace(gtNone,gtNone,CommentEndPos,CommentEndPos,'}');
-      //debugln('Comment {} "',copy(Src,CommentStartPos,CommentEndPos-CommentStartPos));
-      exit;
-    end;
-    // try (*  *)
-    i:=CommentStartPos;
-    while (i<CommentEndPos-1) and ((Src[i]<>'*') or (Src[i+1]<>')')) do inc(i);
-    if i=CommentEndPos-1 then begin
-      SourceChangeCache.Replace(gtNone,gtNone,CommentStartPos,CommentStartPos,'(*');
-      SourceChangeCache.Replace(gtNone,gtNone,CommentEndPos,CommentEndPos,'*)');
-      //debugln('Comment (**) "',copy(Src,CommentStartPos,CommentEndPos-CommentStartPos));
-      exit;
-    end;
-    // do it with // comments
-    SourceChangeCache.Replace(gtNone,gtNone,CommentStartPos,CommentStartPos,'//');
-    SourceChangeCache.Replace(gtNone,gtNewLine,CommentEndPos,CommentEndPos,' ');
-    //debugln('Comment // "',copy(Src,CommentStartPos,CommentEndPos-CommentStartPos));
-    for i:=CommentStartPos+1 to CommentEndPos-1 do
-      if (Src[i-1] in [#10,#13]) and (not (Src[i] in [#10,#13])) then begin
-        SourceChangeCache.Replace(gtNone,gtNone,i,i,'//');
+    CurStartPos:=CommentStartPos;
+    CurEndPos:=CurStartPos;
+    CommentNeeded:=false;
+    repeat
+      if (Src[i]='{') or (i>=CommentEndPos) then begin
+        // the area contains a comment -> comment in front
+        if CommentNeeded then begin
+          SourceChangeCache.Replace(gtNone,gtNone,CurStartPos,CurStartPos,'{');
+          SourceChangeCache.Replace(gtNone,gtNone,CurEndPos,CurEndPos,'}');
+          //DebugLn('Comment "',copy(Src,CurStartPos,i-CurStartPos),'"');
+          CommentNeeded:=false;
+        end;
+        if i>=CommentEndPos then break;
+        // skip comment
+        i:=FindCommentEnd(Src,i,Scanner.NestedComments);
+      end else if not IsSpaceChar[Src[i]] then begin
+        if not CommentNeeded then begin
+          CurStartPos:=i;
+          CommentNeeded:=true;
+        end;
+        CurEndPos:=i+1;
       end;
+      inc(i);
+    until false;
   end;
   
   function CommentUnitsInUsesSection(UsesNode: TCodeTreeNode): boolean;