It does not make sense that xfs would be trying to replay a log from a
partition which has been zeroed, then mkfs.jfs'd - there should be no
xfs superblock magic left, and xfs should not try to do anything.
What do you get from:
dd if=/dev/your/device bs=1 count=4 | strings
if you see "XFSB" in the output, then you still have an xfs superblock.
p.s. actually you have stumbled upon our plan for global domination,
once you have formatted with mkfs.xfs your drive is xfs forever. ;-)
Eric Sandeen [C]XFS for Linux http://oss.sgi.com/projects/xfs
sandeen@xxxxxxx SGI, Inc. 651-683-3102