encrypted swap using alpha

[Bruno Wolff III]

I tried manually setting up partions and had swap using an encrypted raid 1
partition.
The installer compalined about this and bailed out.
Since this is a play install I am going to just let the installer set things
up on the next go around.
But I was wondering if there is some trick to setting up encrypted swap
partitions, or if this is a bug in the installer that is fixed in a later
boot.iso or that needs to be bugzillad?