scroll wheel doesn't work in file dialog

[i1abnrk]

tried to use my scroll wheel to select a file, the mouse scrolls to a point then selects the first file it stops on. I expect to scroll further, repeatedly until I find the correct file descriptor, then use the left-mouse button (or mouse button 1) to choose a file. I'm using ImageMagick 6.7.7-10 for Ubuntu vmlinuz-3.16.0-25-generic.efi.signed/Gnome3 with standard X11 mouse server.