IBM Thinkpad T41 FC4-re0606.1 failed during anaconda when it tried to format my
/home partition.

VT3 says:
* formatting /home as ext3
* Format command: ['/usr/sbin/mke2fs', '/tmp/hda4', '-i', '4096', '-j']

VT5 says:
mke2fs 1.37 (21-Mar-2005)
/tmp/hda4: Invalid argument passed to ext2 library while setting up superblock

GUI dialog says:
An error occurred trying to format hda4.  This problem is serious, and the
installer cannot continue.
Press <Enter> to reboot your system.

sfdisk -d /dev/hda after the failure:
# partition table of /dev/hda
unit: sectors

/dev/hda1 : start=       63, size= 12428577, Id= 7, bootable
/dev/hda2 : start= 12428640, size= 16390080, Id=83
/dev/hda3 : start= 28818720, size=  1043280, Id=82
/dev/hda4 : start= 29862000, size= 48278160, Id=83

Prior to this install attempt, /dev/hda4 was an extended partition containing
two ext3 partitions on /dev/hda5 and /dev/hda6.  I did not modify hda1 (NTFS),
hda2 (/) and hda3 (swap) during this installation attempt.

cat /proc/partitions says:
major minor  #blocks  name

   3     0   39070080 hda
   3     1    6214288 hda1
   3     2    8195040 hda2
   3     3     521640 hda3
   3     4          1 hda4
   7     0      79512 loop0

1 block size on my 24GB /dev/hda4 doesn't look good.

This sounds suspiciously like the problem dcbw complained about on IRC
yesterday, where the kernel failed to see the new partition table on his aic79xx
SCSI /dev/sda, and install failed in a different way.

http://devserv.devel.redhat.com/~dcbw/anacdump.txt
Error informing the kernel about modifications to partition /dev/sda1 - Device
or resource busy.  This means Linux won't know about any changes you made to
/dev/sda1 until you reboot - so you shouldn't mount it or use it in any way
before rebooting.

He also said that /proc/partitions was missing /dev/sda1.

In my case I did manual partitioning, while he used "remove all partitions" from
a disk that previously contained unknown stuff.