The upstream discussion about this has been ongoing for a _very_ long time. Some distros, for example arch, have used downstream patches. See avahi#212 and https://avahi.freedesktop.narkive.com/2Vi2UDCe/daemon-dies-on-certain-hostnames (discussion from 2006!). Upstream seems to have settled on the commit from avahi#523 in 0.9-rc1.