Comment 2 for bug 531539

Confirmed using the advanced installer for lucid beta.
except that typing:
mkswap /dev/mapper/sda3_crypt
was the workaround

also, just a random usability comment: if you want to encrypt some volumes, or if you already have some encrypted volumes that you want to mount, then it is not clear what you should do. If I have an already encrypted volume, then I was worried that by selecting it to be encrypted, it would re-encrypt and my data would be lost.