printf zero-pads strings?

[Paul Williamson]

Has the definition of printf changed since early drafts of the ANSI spec?
In particular, I am interested in the interpretation of 
  printf("%05s", "x");
According to my old draft spec, and several compilers, this should print
"0000x".  That is, it should pad the string on the left with zeroes.  But
K&R2 and several other compilers give "    x", claiming that zero-padding
applies only to numeric values.

I know from my experiments with various compilers that it isn't safe to
use this construct in the real world.  But I can't help but wonder which
compilers are right according to the current pANS.  Language lawyers?

Paul Williamson           williams%cs at ucsd.edu