tuning widgets base size

[Alexander <b3nder yandex ru>]

Hi, list.

I've noticed many widgets calculate its base size relying on font sizes (font size, ascent, descent...) of 
its pango context. Thus I've tried to change PangoFontDescription of widgets in this way just after widget 
creation:

  context = gtk_widget_get_pango_context ( wg );
  descr1 = pango_context_get_font_description ( context );
  descr2 = pango_font_description_copy(descr1) ;

  int size = pango_font_description_get_size(descr2);

  size  = ( size * 2 ) / 3;

  pango_font_description_set_size(descr2, size);
  pango_context_set_font_description(context, descr2); 

But this doesn't work. What is the right solution of my problem? Finaly I want make widgets smaller than 
default widgets, like toolbox widgets in The GIMP. 

Thanks.