Just an FYI - this has been happening to me for about a month or two - 
and I'm running the Amiga port, so this doesn't seem to be arch-specific.

My last attemp would bring up X and the window manager, but I got no
response from the keyboard or the mouse.  What seemed interesting was,
when I fell back to libc.so-12.0 X would work.  With libc.so-12.3 it
no-workie.  I just got back off a two week vacation, so I'm rusty on the
details, but I'll be glad to provide more to whoever thinks they may
know what to look for [ or ask ;-) ].

I'm on an A3000 with 12meg of ram, if that's important - which I'm guessing
it isn't.

-dick