### Please describe the problem.

git annex now fails to transfer a fail with: `protocol version mismatch -- is your shell clean?`

### What steps will reproduce the problem?

start a transfer, then switch between your wireless and wired connexions (I am using network-manager), then interrupt the transfer with control-c.

### What version of git-annex are you using? On what operating system?

on my side: 5.20140306~bpo70 on debian wheezy amd64

on the other side: 4.20130815 on ubuntu saucy i386

### Please provide any additional information below.

[[!format sh """
anarcat@angela:video$ git annex copy --to t films/foo.mkv
copy films/foo.mkv (checking t...) (to t...)
protocol version mismatch -- is your shell clean?
(see the rsync man page for an explanation)
rsync error: protocol incompatibility (code 2) at compat.c(174) [sender=3.0.9]

  rsync failed -- run git annex again to resume file transfer
failed
git-annex: copy: 1 failed
"""]]

workaround: `cd .git/annex/; mv transfer transfer.old` on the other side.

-- [[anarcat]]

> [[fixed|done]] --[[Joey]]