conflict of "exec zsh" with scp

[Andy Spiegl <zsh.Andy@xxxxxxxxx>]

At work all my colleagues prefer bash (I couldn't convince them yet *sigh*).
But I can't live without zsh anymore.  So I put the following into .bashrc:

 if [[ "$REALUSER" == "Andy Spiegl" ]]; then
   which zsh >/dev/null 2>&1 && exec zsh -l
 fi

(the environment variable is coming from .ssh/authorized_keys)

This works great but now scp doesn't work anymore:
 lama:~>scp foo otherhost:
 stty: standard input: Invalid argument
 [1]    19108 exit 1     scp -C foo otherhost:

Any idea how to distinguish my ssh-connects from scp-connects in .bashrc?

Thanks a lot,
 Andy.

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