Can't update or use package manager -- gpg error

在更新源的时候，出现以下信息：

W: GPG error: karmic Release: Unknown error executing gpgv
W: GPG error: karmic Release: Unknown error executing gpgv
W: GPG error: karmic-updates Release: Unknown error executing gpgv
W: GPG error: karmic-security Release: Unknown error executing gpgv
W: GPG error: karmic-proposed Release: Unknown error executing gpgv

I fought this problem from synaptic on down to gpg, only to find it was readline all along. My solution was somewhat simpler than building or patching.

in terminal:

ls /usr/local/lib

there was a bunch of readline libs in there (libreadline.so.BLAH-BLAH) so i:

su
mkdir temp
mv /usr/local/lib/libreadline* temp
ldconfig
apt-get update

and voila. went without a hitch. then i deleted my temporary directory (rm -rf /usr/local/lib/temp), exited su.

~2 hours fighting to no avail, and for it work with a few seconds of commands...
I'm not complaining, but it does seem somewhat of a cruel irony.