Can't release for a version that already has a milestone

If I try to "quickly release" with a version number that already has a milestone in my LP project, I get the following error (after code is pushed and a package is uploaded to the PPA). It should probably make this check earlier and allow it if the milestone is active, error out if it it's inactive.

Traceback (most recent call last):
  File "/home/mike/Code/quickly/quickly/data/templates/ubuntu-application/release.py", line 287, in <module>
    release_version), changelog)
  File "/home/mike/Code/quickly/quickly/data/templates/ubuntu-application/internal/launchpad_helper.py", line 57, in push_tarball_to_launchpad
    release = create_release(project, version)
  File "/home/mike/Code/quickly/quickly/data/templates/ubuntu-application/internal/launchpad_helper.py", line 44, in create_release
    date_targeted=release_date)
  File "/usr/lib/python2.7/dist-packages/lazr/restfulclient/resource.py", line 573, in __call__
    url, in_representation, http_method, extra_headers=extra_headers)
  File "/usr/lib/python2.7/dist-packages/lazr/restfulclient/_browser.py", line 281, in _request
    raise error
lazr.restfulclient.errors.BadRequest: HTTP Error 400: Bad Request
Response headers:
---
-content-encoding: gzip
connection: close
content-length: 75
content-type: text/plain;charset=utf-8
date: Mon, 12 Sep 2011 18:34:52 GMT
server: zope.server.http (HTTP)
status: 400
vary: Accept,Accept-Encoding
via: 1.1 api.staging.launchpad.net
x-lazr-notifications: []
x-powered-by: Zope (www.zope.org), Python (www.python.org)
---
Response body:
---
name: The name 9.0 is already used by a milestone in Multiplication Puzzle.
---

ERROR: release command failed
Aborting