Attaching style to Labels inside Buttons

[Zeeshan Ali <zeenix gmail com>]

Hello,
   What would be the gtkrc line to attach a style 'foo' to all the
labels that are inside buttons. I tried the following but none of them
worked:

class "GtkButton.*.GtkLabel" style "foo"
widget "GtkButton.*.GtkLabel" style "foo"
class "GtkButton.GtkLabel" style "foo"
widget "GtkButton.GtkLabel" style "foo"
etc etc

    Thanks in advance. Bye.