If I recall correctly, 'indir' was a program designed to indirectly 
execute other programs.  My recollection is that it was supposed to be 
particularly useful in setuid situations where the OS didn't natively 
provide you much help, and/or perhaps in situations where the OS kernel 
limited you to 32 character command lines.

> Personally I wouldn't object to the removal of this exec feature. But
> at the very least shouldn't we document that "indir" thing ?

I don't think indir is actively maintained, and we don't recommend
doing setuid scripts this way anymore either, so removing the 'indir' 
special case is probably appropriate.