Reassigning to gtk+3.0, this was introduced with gtk 3.4.2 which included a change for finding symbolic icons.
http://git.gnome.org/browse/gtk+/commit/gtk/gtkicontheme.c?id=271adacfadfdd81b27fb12356fe20cde3094de37
I have reproduced this with 3.4.2-0ubuntu0.1 in precise-proposed and 3.4.2-0ubuntu1 in quantal
Reassigning to gtk+3.0, this was introduced with gtk 3.4.2 which included a change for finding symbolic icons.
http:// git.gnome. org/browse/ gtk+/commit/ gtk/gtkiconthem e.c?id= 271adacfadfdd81 b27fb12356fe20c de3094de37
I have reproduced this with 3.4.2-0ubuntu0.1 in precise-proposed and 3.4.2-0ubuntu1 in quantal