gdk_pixmap de/allocation

[Markus Lausser <sgop users sourceforge net>]

HEllo.

I am drawing a pixmap in a gtk_ctree:
I have the following line:
  gtk_ctree_node_set_pixmap(ctree, node, 5, pixmap, NULL);

The pixmap is allocated as followed:
  If there is no pixmap in the ctree cell yet or the column width
  has changed then i allocate a new pixmap, otherwise i draw only the
  context changes in the existing one.

Now my question: do i have to deallocate the old pixmap or something?
i cant find any pixmap deallocation function, for now i only 
gtk_pixmap_unref() on the old pixmap. Is that enough?

Markus.