> You don't have to put gzip in the pipeline.  Gpg compresses data by default
  > (zlib level 6, according to gpg(1)), before doing encryption.

  Excellent. Is there an official way of encrypting amanda, or just doing it 
  this way?

Note that there is also support for using krb4 to encrypt the stream
over the network, but this results in cleartext backups on the holding
disk and on tape.  It's also hard to set up if you don't already grok
kerberos.

-- 
        Greg Troxel <gdt AT ir.bbn DOT com>