[ESS] Emacs crashes when commenting code in ESS mode

[Sven Garbade]

Dear all,

from time to time I observed following problem: when commenting Latex
code outside a code chunk in a .Rnw file (with C-x comment-region),
emacs consumes much cpu power (>50%) and never ends, I have to kill
emacs. I never observed this problem without ESS. Maybe this is auctex
related? Other Ideas?

emacs version 24.2, ESS 12.9 on gentoo Linux

Thanks, Sven