This is a backport of missing chunk of the patch:

Author:	qulogic@pidgin.im
Changelog:	I guess this pref name was changed but this one line was not. This would
cause the status icon theme to revert to the default on startup.
Fixes #10155.
Date:	Tue, 01 Sep 2009 00:33:52 GMT
#
#
# patch "pidgin/pidginstock.c"
#  from [2487a2d68312f5afff439a0fa765c3fe40553701]
#    to [d1da5e342d29fffdf381c68b779c2cb80c5e2caf]
#
Index: pidgin-2.6.2/pidgin/pidginstock.c
===================================================================
--- pidgin-2.6.2.orig/pidgin/pidginstock.c
+++ pidgin-2.6.2/pidgin/pidginstock.c
@@ -609,7 +609,8 @@ pidgin_stock_init(void)
 
 		PidginStatusIconTheme *theme = PIDGIN_STATUS_ICON_THEME(purple_theme_loader_build(PURPLE_THEME_LOADER(loader), path));
 		pidgin_stock_load_status_icon_theme(theme);
-		g_object_unref(G_OBJECT(theme));
+		if (theme)
+			g_object_unref(G_OBJECT(theme));
 
 	}
 	else