Hi,
The issue was marked as resolved, but is not yet fixed. I cannot reopen it nor add notes there, so I post here. I uploaded some files there though.
If doesn't work if there are images of different size in each menu item and if images are not square (see wrong2.png), I have uploaded another example to show that (example_rect_imgs.tar.bz2). Look at Form2 menus, in Main Menu and in Popup Menu.
I have uploaded another patch named patch02.diff (to rev. 23989). It lets GTK handle calculating toggle_size of each menu item and for the menu class. It returns size of the "toggle" icon based on image size on 'toggle-size-request' signal. Also I have made a small change to drawing icon, it now calculates left position the same as in GTK2.
cobines