First do the obvious stuff:
sudo mount --bind /opt /var/iso/build-etch/opt
sudo mount --bind /home /var/iso/build-etch/home
sudo chroot build-etch
su markus


to avoid a man page error:
export LC_ALL=de_AT.UTF-8
export LANG=de_AT.UTF-8

Warning!
Make sure to source cc for 32bit and cce for 64 bit.
For 64bit ia32-libs need to be installed.
This is for 64bit:

source /opt/intel/cce/10.1.018/bin/iccvars.sh

(dont source again, PATH and so on will be written double)

now export compiler:
export CC=icc
export CXX=icpc