How to add paddings to a widget before gtk+2.4?

[gniuxiao <gniuxiao mailinglist gmail com>]

Hi, I may wrap a widget with an GtkAlignment, and then use
gtk_alignment_set_padding to add top/right/bottom/left paddings to the
wrapping GtkAlignment in gtk+2.4 or higher version, but how to do the
same thing before 2.4? That is, how to add paddings to a widget?

I have to make my program run on gtk+2.2.

Thanks.