Scrolling in pc-selection mode with scroll-margin broken

[Eugene Vlasov]

Symptoms:

I notice strange scrolling with PgDn (bound to scroll-up-nomark) in
pc-selection-mode with nonzero value of scroll-margin, i.e.:

1. I have (setq scroll-margin 5) in my ~/.emacs,
2. file has 60 lines and 57 top lines visible in window,
3. point in line 1,
4. I press PgDn:
point looks somewhere in middle window, but in status line "94%
(60,0)". And I can't see bottom 3 line with PgDn.


In GNU Emacs 22.0.50.1 (i686-alt-linux-gnu, GTK+ Version 2.8.3)
 of 2005-09-19 on eugene-home.ikz.ru
X server distributor `The X.Org Foundation', version 11.0.60899900
configured using `configure '--build=i686-alt-linux' '--host=i686-alt-linux' 
'--prefix=/usr' '--exec-prefix=/usr' '--bindir=/usr/bin' '--sbindir=/usr/sbin' 
'--sysconfdir=/etc' '--datadir=/usr/share' '--includedir=/usr/include' 
'--libdir=/usr/lib' '--libexecdir=/usr/lib' '--localstatedir=/var/lib' 
'--sharedstatedir=/usr/com' '--mandir=/usr/share/man' 
'--infodir=/usr/share/info' '--without-included-gettext' 
'--sharedstatedir=/var' '--with-gcc' '--with-pop' '--with-x-toolkit=gtk' 
'--with-png' '--with-jpeg' '--with-xpm' '--with-gif' '--with-tiff' 
'CFLAGS=-pipe -Wall -O2 -march=i686' 'build_alias=i686-alt-linux' 
'host_alias=i686-alt-linux''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: ru_RU.KOI8-R
  locale-coding-system: cyrillic-koi8
  default-enable-multibyte-characters: t

Major mode: Text

Minor modes in effect:
  flyspell-mode: t
  display-time-mode: t
  recentf-mode: t
  encoded-kbd-mode: t
  delete-selection-mode: t
  pc-selection-mode: t
  show-paren-mode: t
  mouse-wheel-mode: t
  tooltip-mode: t
  auto-compression-mode: t
  menu-bar-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
M-x <up> <down> r e p o r t <tab> <return>

Recent messages:
Loading /home/eugene/.recentf...done
Cleaning up the recentf list...done (0 removed)
Loading time...done
Loading desktop...done
No desktop file.
Loading /home/eugene/.session...done
Loading flyspell...done
Starting new Ispell process...
For information about the GNU Project and its goals, type C-h C-p.
Loading emacsbug...done