[...]
> I'm on Debian testing/AMD64, did a test with an old C2D 8400P laptop
> and a new one with Core i5 2410, both have 4G of memory and the same
> installation (Fluxbox, Mutt, Google Chrome and some console
> applications).
You must try with the more recent packge in unstable.
If the crash is still here, you must report this bug to the upstream
author.