The author was able to clue me in to the issue here. I think it was a "documentation bug". :) Adding this to my options fixed it:

homedir => /path/to/.gnupg

also adding: trace => 1 produced some useful debugging output.

In reply to RE: GnuPG::Tie::Encrypt failing (fixed) by markjugg
in thread Favorite PGP module for web-to-email forms? by markjugg

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