Window recentering on wrapped lines

[digifork]

I am using emacs 21.1.1 on Windows 2000 and Solaris 8, but the behavior I'm
about to describe has existed in previous versions of emacs on different
platforms as well.

It seems that the line-wrap logic in emacs does not consider the values of
the scroll-step or scroll-conservatively settings, thus recentering the
buffer when part of a wrapped line is off the screen.

I have the following variables set in my .emacs file:

(setq truncate-partial-width-windows nil)
(setq scroll-step 1)
(setq scroll-conservatively 1000000)

The desired result of those lines is when using the arrow keys to move up
and down through a file, I don't want to have to scroll side to side to see
a line in it's entirety and I want to be able step through the file one line
at a time with no recentering.

The problem is encountered when I am scrolling up or down with the arrow
keys, my cursor is a the top or bottom of the screen, and it reaches a line
that has been line-wrapped. I cannot find any setting to fix this behavior.

Am I correct in assuming that this is a bug?

Thanks!
-digi