I just tried booting a PowerMac G4 with the Wheezy installer image
"built on 20120826-03:23" (details of where I downloaded it from,
etc available on request).
The G4 is a 32-bit machine, but it seems to be offering me the
choices for a 64 bit machine.
Before the "boot:" prompt it said (among other things)
install 64-bit processor (G5 or POWER3/4/5/6/7)
install32 32-bit processor (G4 or earlier)
and when I entered <tab> at the "boot:" prompt I saw the list of
options
install expert rescue
auto install32 expert32
rescue32 auto32
If I just hit <ret> at the "boot:" prompt it looks like it's trying
to boot the 64-bit kernel, which (of course) fails on the G4.
The only unusual thing about this is that I'm booting from a USB
stick using Open Firmware, rather than from a physical CD-ROM.
Should that make any difference?