GBDE filesystem not recognised in 5.3-BETA5?

I'm seeing a pretty major regression between 5.3-BETA1 and 5.3-BETA5.
I'm also hoping that I have done something stupid, but I don't see what.

On my laptop, /usr/home is a GBDE backed filesystem, which is working
find on 5.3-BETA1:

FreeBSD falken.private.submonkey.net 5.3-BETA1 FreeBSD 5.3-BETA1 #6: Mon Aug 23 17:59:03 BST 2004     root_at_falken.private.submonkey.net:/usr/obj/usr/src/sys/FALKEN  i386

I've updated to 5.3-BETA5 and am seeing the following:

   # uname -a
   FreeBSD  5.3-BETA5 FreeBSD 5.3-BETA5 #8: Sun Sep 19 17:13:59 BST 2004     root_at_falken.private.submonkey.net:/usr/obj/usr/src/sys/FALKEN  i386
   # /etc/rc.d/gbde start
   Configuring Disk Encryption for /dev/ad0s2f.bde.
   Enter passphrase: 
   # mount /usr/home
   mount: /dev/ad0s2f.bde on /usr/home: incorrect super block
   # fsck /dev/ad0s2f.bde
   ** /dev/ad0s2f.bde
   Cannot find file system superblock
   ioctl (GCINFO): Inappropriate ioctl for device
   fsck_ufs: /dev/ad0s2f.bde: can't read disk label
   # 

Pointing fsck at an alternative superblock has no effect - it refuses to
read any of them.

Booting the 5.3-BETA1 kernel has the filesystem working fine again.

What changed/what did I do wrong?

Ceri
-- 
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