install/47818: 6.1_RC4 installation ISO hangs at boot on VirtualBox

[mw%wzff.de@localhost]

>Number:         47818
>Category:       install
>Synopsis:       6.1_RC4 installation ISO hangs at boot on VirtualBox
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    install-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Wed May 15 11:05:00 +0000 2013
>Originator:     Moritz Wilhelmy
>Release:        6.1_RC4
>Organization:
>Environment:
NetBSD 6.1_RC4 boot.iso from 
ftp://ftp.netbsd.org/pub/NetBSD/NetBSD-6.1_RC4/i386/installation/cdrom/ (32-bit)
on VirtualBox VirtualBox-4.2.10-84105 on Windows XP (32-bit)
>Description:
The boot hangs with the following message:

...[snip]...
midi0 at pcppi0: PC speaker
sysbeep0 at pcppi0
isapnp0 at isa0 port 0x279
npx0 at isa0 port 0xf0-0xff
attimer0: attached to pcppi0
uvm_fault(0xc0c8c9e0, 0, 1) -> 0xe
fatal page fault in supervisor mode
trap type 6 code 0 eip c0100e28 cs 8 eflags 246 cr2 0 ilevel 0
kernel: supervisor trap page fault, code=0
Stopped in pid 0.1 (system) at netbsd:spllower+0x28:    addb    %al,0(%eax)
db{0}>
>How-To-Repeat:
Boot boot.iso in VirtualBox
>Fix: