IOTAHighlighter not calling Tokenize

Question

I'm trying to write a simple highlighter (which adds highlighting a certain kind of variable in a pas-file)

I used the code in http://www.delphi-central.com/syntax_highlighting.aspx

problem is that the Tokenize procedure is never called. It does get registered in the Register procedure by:

RegisterPackageWizard(TSimpleHighlight.Create);

or alternatively in the constructor by:

(BorlandIDEServices As IOTAHighlightServices).AddHighlighter(TSimpleHighlight.Create);

and GetName gets called when I launch the menu Tools.Options

code snippet:

TSimpleHighlight = class(TNotifierObject, IUnknown, IOTANotifier, IOTAHighlighter, IOTAWizard)
public
  function GetIDString: string;
  function GetName: string;
  procedure Tokenize(StartClass: TOTALineClass; LineBuf: POTAEdChar;
    LineBufLen: TOTALineSize; HighlightCodes: POTASyntaxCode);
  function TokenizeLineClass(StartClass: TOTALineClass;
    LineBuf: POTAEdChar; LineBufLen: TOTALineSize): TOTALineClass;
  function GetState: TWizardState;
  procedure Execute;
  constructor Create;
end;

procedure Register;
begin
  RegisterPackageWizard(TSimpleHighlight.Create);
end;

constructor TSimpleHighlight.Create;
begin
  inherited;
  (BorlandIDEServices as IOTAHighlightServices).AddHighlighter(Self);
end;

The tutorial mentions "Using OTA you can create highlighters for new source file types." so do I have to register this for pas-files somehow, or am I missing something else?