acroread freezes with Gtk-WARNING

[Pancho]

acroread freezes right on startup. I've not used it within the last weeks, but before upgrading to Jaunty I'm quite sure it worked well.
I'm getting the following error messages as normal user vs. su

$ acroread
Xlib: extension "RANDR" missing on display ":0.0".
(acroread-deu:21870): Gtk-WARNING **: /usr/lib/gtk-2.0/2.10.0/engines/libqt4engine.so: wrong ELF class: ELFCLASS64
(acroread-deu:21870): Gtk-WARNING **: /usr/lib/gtk-2.0/2.10.0/engines/libqt4engine.so: wrong ELF class: ELFCLASS64

# acroread
Xlib: extension "RANDR" missing on display ":0.0".

In both cases acroread starts but is frozen, disallowing any UI action. If started with a document, the document is opened and rendered, before acroread freezes.
I'm running Jaunty with all the latest updates. My graphics card doesn't support RANDR, but that shouldn't be the problem.

[Pancho (pancho.s)]

Just an addition:
I'm getting the message:
Xlib: extension "RANDR" missing on display ":0.0".
with all other GTK applications as well, and they do work. I already mentioned that I had acroread already working on this machine. So RANDR is definitely not the problem. Just disregard the line.

[Pancho (pancho.s)]

Confirmed on a second (RANDR-enabled) machine running Jaunty:

$ acroread
(acroread-deu:21979): Gtk-WARNING **: /usr/lib/gtk-2.0/2.10.0/engines/libqt4engine.so: wrong ELF class: ELFCLASS64
(acroread-deu:21979): Gtk-WARNING **: /usr/lib/gtk-2.0/2.10.0/engines/libqt4engine.so: wrong ELF class: ELFCLASS64

Same error.

[Erik Harren (linux-aceh)]

I confirm it as well in Jaunty:

Gtk-Message: Failed to load module "canberra-gtk-module": /usr/lib/gtk-2.0/modules/libcanberra-gtk-module.so: wrong ELF class: ELFCLASS64