deleting a recipe causes an oops

Trying to remove a recipe (https://code.edge.launchpad.net/~jelmer/+recipe/ppa-lucid/+delete) I get the following exception (OOPS OOPS-1634EC3847):

Traceback (most recent call last):

Module zope.publisher.publish, line 134, in publish
Module canonical.launchpad.webapp.publication, line 436, in callObject
return mapply(ob, request.getPositionalArguments(), request)
Module zope.publisher.publish, line 109, in mapply
__traceback_info__: <security proxied zope.browserpage.metaconfigure.SimpleViewClass from /srv/edge.launchpad.net/edge/launchpad-rev-11042/lib/lp/code/browser/../../app/templates/generic-edit.pt instance at 0x2aaab6c16090>
Module zope.publisher.publish, line 115, in debug_call
Module canonical.launchpad.webapp.publisher, line 274, in __call__
self.initialize()
Module canonical.launchpad.webapp.launchpadform, line 111, in initialize
self.form_result = action.success(data)
Module zope.formlib.form, line 606, in success
Module lp.code.browser.sourcepackagerecipe, line 497, in request_action
self.context.destroySelf()
Module lp.code.model.sourcepackagerecipe, line 185, in destroySelf
destroyBuilds(pending=True)
Module lp.code.model.sourcepackagerecipe, line 184, in destroyBuilds
build.destroySelf()
Module lp.code.model.sourcepackagerecipebuild, line 222, in destroySelf
job = self.buildqueue_record.job
AttributeError: 'NoneType' object has no attribute 'job'<br />