can't proxy older gcr.io docker images

$ curl https://gcr.io/v2/google_containers/leader-elector/manifests/0.5 -H 'Accept: application/vnd.docker.distribution.manifest.v2+json'
{"errors":[{"code":"MANIFEST_UNKNOWN","message":"Manifest with tag '0.5' has media type 'application/vnd.docker.distribution.manifest.v1+prettyjws', but client accepts 'application/vnd.docker.distribution.manifest.v2+json'."}]}

$ curl -s -o /dev/null -w "%{http_code}" https://gcr.io/v2/google_containers/leader-elector/manifests/0.5 -H 'Accept: application/vnd.docker.distribution.manifest.v2+json'
404
$ docker pull gcr.docker.foo.com/google_containers/leader-elector:0.5
Error response from daemon: digest invalid: provided digest did not match uploaded content

$ curl -s -o /dev/null -w "%{http_code}" https://gcr.io/v2/google_containers/leader-elector/manifests/0.4 -H 'Accept: application/vnd.docker.distribution.manifest.v2+json'
200
$ docker pull gcr.docker.foo.com/google_containers/leader-elector:0.4
0.4: Pulling from google_containers/leader-elector
...

$ curl -s -o /dev/null -w "%{http_code}" https://gcr.io/v2/google_containers/echoserver/manifests/1.4 -H 'Accept: application/vnd.docker.distribution.manifest.v2+json'
404
$ docker pull gcr.docker.foo.com/google_containers/echoserver:1.4
Error response from daemon: digest invalid: provided digest did not match uploaded content

$ curl -s -o /dev/null -w "%{http_code}" https://gcr.io/v2/google_containers/echoserver/manifests/1.10 -H 'Accept: application/vnd.docker.distribution.manifest.v2+json'
200
$ docker pull gcr.docker.foo.com/google_containers/echoserver:1.10
1.10: Pulling from google_containers/echoserver
...

$ curl -s -o /dev/null -w "%{http_code}" https://gcr.io/v2/google_containers/node-problem-detector/manifests/v0.2 -H 'Accept: application/vnd.docker.distribution.manifest.v2+json'
404
$ docker pull gcr.docker.foo.com/google_containers/node-problem-detector:v0.2
Error response from daemon: digest invalid: provided digest did not match uploaded content

$ curl -s -o /dev/null -w "%{http_code}" https://gcr.io/v2/google_containers/node-problem-detector/manifests/v0.5.0 -H 'Accept: application/vnd.docker.distribution.manifest.v2+json'
200
$ docker pull gcr.docker.foo.com/google_containers/node-problem-detector:v0.5.0
v0.5.0: Pulling from google_containers/node-problem-detector
...