Note that you can probably pretty much replicate the Kindle toolchain (gcc 4.1.2/glibc 2.5/Linux 2.6.22) with ct-ng if you enable the 'deprecated' option, no need to build it manually from amazon's tarballs.
And, unless you intend to build a whole lot of crap, you'll probably be good to go with a recent TC. I haven't yet hit a real TC related ABI mismatch showstopper with what I built so far.
And I'm really, really not a fan of using a 3.5 years old TC, so I'm glad I haven't had to use a GCC 4.1 based TC
.
Granted, with a kindle-like (ie. old) TC, at least you'll be mostly 100% sure it will run without issue on the Kindle, which is not really the case with my current TC, but, hey, where's the fun in that?
.