Something in the recent updates from 1.4.7 must have broken the death messages further because now I have noticed on my server death messages appear in chat e.g. "death.attack.kar98kAmmo" or "death.attack.g3Ammo".

I believe the "death.plane" message has changed to "death.attack.plane" too.

Edit
What should be happening is a death message with icons in the bottom left corner e.g. player1 gunicon player2.

I have also experienced this issue.

Fixed by flan in latest source.