missing dependency in gnupg2

[paul beard]

gnupg2 2.0.3, mail/gnupg2 (Variants: universal, darwin, darwin_7)
http://www.gnupg.org

GnuPG is a complete and free replacement for PGP. Because it does not  
use the patented IDEA algorithm, it can be used without any  
restrictions. GnuPG is a RFC2440 (OpenPGP) compliant application.

Library Dependencies: libiconv, gettext, zlib, bzip2, bison,  
libassuan, libksba, libgcrypt, libgpg-error, pth
Platforms: darwin freebsd sunos
Maintainers: waqar at macports.org

Apparently, gnupg2 expects gpg-agent to be installed:

can't connect server: `ERR 33554701 can't exec `/opt/local/bin/gpg- 
agent': No such file or directory'
gpg: can't connect to the agent: IPC connect call failed
gpg: problem with the agent: No agent running