a2ps configure error

[Igor Gueths]

Hi. I am unable to make a2ps because of the following error, which in turn
resulted in the premature termination of the configure script: Cannot find
output from ${SHELL}
/usr/local/a2ps-4.13/auxdir/
missing --run flex; giving up.

        This problem was not documented at
www.inf.enst.fr/~demaille/a2ps/bugs.html. Running Debian Gnu Linux 2.2,
kernel 2.4.18-i686 architecture. Gcc 3.0.4 c/c++ compiler.