sort parameters question: -V and -f

[Assaf Gordon]

Hello,

I'm wondering if this is a bug (where "-f" is ignored when using version sort):

=========
$ sort --debug -f -k2,2V 
sort: using simple byte comparison
sort: leading blanks are significant in key 1; consider also specifying `b'
sort: option `-f' is ignored
==========

My assumption is that using "-f" as stand alone parameter should have the same 
effect as using it in a specific key (for that key). e.g. the following two 
commands are equivalent:
 sort -f -k1,1
 sort -k1f,1

But the following two commands are not equivalent (because the standalone "-f" 
is ignored):
 sort -f -k1V,1
 sort -k1Vf,1

Example:
=================

## This works
$ printf "a\nB\nc\n" | sort -k1f,1
a
B
c
$ printf "a\nB\nc\n" | sort -f -k1,1
a
B
c

## This doesn't work
$ printf "a13\nA5\na1\n" | sort -k1Vf,1
a1
A5
a13

$ printf "a13\nA5\na1\n" | sort -f -k1V,1
A5
a1
a13
===================

I'm using coreutils 8.10.

-gordon