--prefix and --exec-prefix

I just managed to install tetex but there were a lot of hang-ups, for
instance, it appears that even though I specify a special prefix for
architecture independent executables with ./configure --prefix=$PREFIX
--exec-prefix=$EPREFIX, it installs many binaries in
$EPREFIX/bin/i686-pc-linux-gnu, rather than $EPREFIX/bin as I was led
to believe by reading the output of ./configure --help and by
experience with other programs. I suppose that I might have the same
problem even if I only used --prefix, but I haven't tried.

Anyway, it would of course be more convenient for users if these
configuration options worked the way they usually do, is there a
reason for tetex to be incompatible?

Frederik

P.S. It would be particularly convenient if generic autoconf-based
tools such as 'toast' worked, as in

GET http://toastball.net/toast/toast|perl -x - arm tetex-src-2.0.2.tar.gz

but I'm not sure if this approach fails due to problems with toast, or
due to the above problem with tetex.