[gtkmm] Into + gdk_pixmap question

["Mortella" <mortella freestart hu>]

Hi everybody !

I am Laszlo Bathory (aka. mortella) from Hungary . Am 28 years old
application developer.
I started to make a powerfull beautiful ftp client in c + gtk  Some weeks
ago I decided to switch the project to c++ and gtkmm because I felt my
sources a bit "out of hand" . I hoped that well designed classes would make
easier my work.
It is ! :-))
My only serious problem is change the gtk elements to gtk--.
My first question is that why:
Gdk_Pixmap *icon;
icon= new Gdk_Pixmap(NULL,NULL.NULL,filename)

produces:
PixButton.cc:26: no matching function for call to
`Gdk_Pixmap::Gdk_Pixmap(NULL,
   NULL, NULL, std::string&)'

More simple I can not call any Gdk_Pixmap constructors,
e.g. new Gdk_Pixmap(1,1,-1) produces :
usr/include/gdk--/types.h: In constructor `PixButton::PixButton(char*,
   char*)':
/usr/include/gdk--/types.h:277: `static void* Gdk_Handle<GdkObj>::operator
   new(unsigned int) [with GdkObj = GdkDrawable]' is private
PixButton.cc:26: within this context

this consturctor is public !!!

I tried to make a trick as well, getting the pixmap from a Gtk::Pixmap but
it seems not to work as well:
Gtk::Pixmap *icon = new Gtk::Pixmap(filename);
Gdk_Pixmap anypix;
Gdk_Bitmap anymask;
icon->get(anypix, anymask);    //<<< seems not working
Gtk::Pixmap anyelse;
anyelse.set(anypix, anymask); //<<< or this doesnt work I dunno:))

icon is the right icon I want from the xpm but anyelse is a gtk dummy pixmap
:(

These worked in gtk. Any idea ?
I would like to got an answer to this , and not imlib (or gtkmm2) etc
solutions.

Thanks
morti