stdout, stderr redirection

Hi all,
can someone help me with the next redirection?
i want to redirect the stdout+stderr of a command to the same file (this i can do by prog &> file)
but in addition i want to redirect only the stderr to a different file.

how can i do this please? (in BASH)
thanks.

command  >stdout.file 2>stderr.file  # redirect each to their own file

Hi,
thanks for the reply,
but,
i want the stdout+stderr to be redirected together to the same file (std_out_err.file) in the origina, program output order, and in addition only the stderr to another file stderr.file

((command | tee out.txt) 4>&2 2>&1 1>&4 | tee err.txt) 2> out_err.txt 1>&2

thanks!