I just upgraded a computer from suse11.2 to 11.4 and the encrypted home wouldn’t mount; I too the entry from cryptotab which used twofish256 and couldn’t understand why an apparently equivalent entry in crypttab didn’t work…

I was seeing this error in dmesg

[ 3871.554336] device-mapper: table: 253:0: crypt: Error allocating crypto tfm
[ 3871.554340] device-mapper: ioctl: error adding target to table

The error on the command line was this:
device-mapper: reload ioctl failed: No such file or directory

After much googling I stumbled on your webpage and fixed it, my crypttab now looks like this:

#cr_home /dev/md4 none cipher=twofish256
cr_home /dev/md4 none cipher=twofish-cbc-plain,size=256,hash=sha512

so thank you ever so much, I spent over half an hour trying to find the answer and I have to admit I was beginning to panic!!!