The left and right mouse buttons in the scroll bar not working

[Yury Georgievskiy]

Hello. I've got Emacs 21.3.1
Normally, 'Mouse-1' should move the line up and 'Mouse-3' should
move down when clicking in the scrollbar.
In my case - bar is always moving only towards the mouse cursor.
What should I do to achive normal mouse behaviour?

Scrollbar appearance is with up' and 'down' arrows on each of the
top. May be this is the reason? Because when I start another
emacs (21.2.1) on another machine - scrollbar appears without 'up'
and 'down' arrows and mouse behaves normally (i.e.
'Mouse-1' - line up, 'Mouse-2' - line down).

Please, if it's possible, email me directly.
Thanks in advance,
Yury.