Still remains a concern to me in 1.4.5. Copious thanks for reminding me to update this - hopefully I'll learn to keep my issues up-to-date from now on. 🙂
But, yes. Please fix this. It's nasty because I like socializing with distant friends via the miracle of the microphone, and push-to-talk is a requirement to me.
Seems to be fixed in the latest development snapshot I just tried (snapshot 13w25a), played via the new launcher.
EDIT: Tried updating the issue after confirming this still affects the "old launcher" version 1.5.2, but couldn't add that to the affected versions list due to error claiming such a version tag doesn't exist.