What steps will reproduce the problem?

Don't have gpg installed/on your $PATH, and attempt to create an encrypted S3 remote via the web interface.

What is the expected output? What do you see instead?

Expected to be told to install GPG. Actual output was a Yesod error:

Internal Server Error user error (gpg ["--batch","--no-tty","--use-agent","--quiet","--trust-model","always","--gen-random","--armor","1","512"] exited 127)

What version of git-annex are you using? On what operating system?

3.20130107 on Fedora 17 (64-bit).

Please provide any additional information below.