Gtk::SpinButton - text?

[Andreas Volz <lists brachttal net>]

Hi,

is there a way to insert a string "not available" or "n/a" in a
Gtk::SpinButton? I tried this, but it doesn't work:

    spin_button.set_sensitive (false);
    spin_button.set_numeric (false);
    spin_button.set_text ("not available");

regards
Andreas