<literal>$FOO</literal> may appear as
separate word on the command line in
which case the variable is replaced by
- its value split at
- whitespaces.</para></listitem>
+ its value split at whitespaces. Note
+ that the first argument (i.e. the
+ binary to execute) may not be a
+ variable, and must be a literal and
+ absolute path name.</para></listitem>
</varlistentry>
<varlistentry>