Though I cannot reproduce it, this has been happening to me throughout the betas.
70f WinXP SP2 I have the Taglist window open (though I don't believe it is related). So my window is split vertically. My cursor is in normal mode in the right hand pane. If I scroll the mouse wheel, the window in the left hand pane scrolls. I hit escape, click, ... tried everything and just cannot get it to scroll the window my cursor is in. Any ideas or things to check for to track it down? Thanks, Dave