There's a small bug in org-mew.el, which appears when trying to store
links to messages which have been marked for refile. I try to be as
clear as possible:

First, a working case:

when storing a link to a message on an IMAP server, the result is like
this:

[[mew:UTU:%inbox#20081117.115043.144292908.harri.kiiskinen@utu.fi][Email
from Harri Kiiskinen: test]]

which is exactly as it should be: First the link type ("mew:"), then
the mew case and the folder name ("UTU:%inbox"), and then the Message
ID. (This is a message I sent to myself.)
Link type: "mew:"
mew case: "UTU:"
folder: "‰inbox"
message id: "#20081117......"

Now, I set the refile mark on the message, and create a new link to
it. The result is:

[[mew:%2008#20081117.115043.144292908.harri.kiiskinen@utu.fi][Email
from Harri Kiiskinen: test]]

Now, the mew case is still set to UTU, meaning that mew will refile
the message to folder UTU:%2008, but the link that is created by
org-mew-store-link does not include the case information. We have:
Link type: mew:
case: (empty)
folder: %2008
message id: (the rest)

I'm no quite able to figure where the bug might be, but I'll keep
trying.

Harri K.