I've seen exactly the same symptoms with Karmic and now also with Lucid.
Apparently what happens is that gnome-keyring-daemon starts correctly at
the beginning of a new session, but eventually exits silently. This
happened to me today in the session from which I'm typing this; gnome-
keyring-daemo
I don't have a fix for this problem, but I did just find a workaround:
1) start gnome-keyring-daemon manually; e.g., from a shell prompt,
type
/usr/bin/gnome-keyring-daemon --start
2) assuming that $SSH_AUTH_SOCK is pointing to the socket created by
the old (now defunct) in
Oops, I was a bit quick on the trigger -- $SSH_AUTH_SOCK points directly
to the socket, not to the directory containing it. :-( The correct
workaround is as follows (i.e., this is a correction to comment #9
above):
/usr/bin/gnome-keyring-daemon --start
newsockdir=`ls -dt1 /tmp/keyring* | head -1`
