[fpc-pascal] constructor overloads - only class methods can ..?

[Wolfram Kläger]

>From time to time I get the error, "only class methods can be referred with class references".  While always managed to get a workaround, I am still not able to understand exactly when this happens and why. Example:

type
  TmyClass = class(TObject)
  private
    ..
  public
    constructor Create; overload;
    constructor Create(AParam : TAny); overload;
    constructor Create(AParam : TAnother); overload;
   ...
   procedure DoImportant(...)
  ...
  end;

procedure TmyClass.DoImportant(...);
var
  Temp : TmyClass;
begin
  ...
  Temp := TmyClass.Create(AParam); // error

Calling the same constructor from a separate unit, everything is fine, without error. Can somebody deliver the clue?

Thanks in advance
Wolfram

BTW: Of course, overloading requires unique param type lists. But why is it impossible to overload functions by unique result type?