Recommitted this commit yesterday, was apparently done in the wrong

directory... so the slowdown was still evident!

Maintenance commit;

  - *Giant* speedup for LMB frame-dragging in ipo/action/nla windows. It was
    calling a routine that accessed frontbuffer drawing.... a very old patch
    for SGIs even! :)
  - Prepared code for support of unlimited Shape keys
  - Curve objects didnt draw correct for selection-outline option

source/blender/src/space.c

@@ -1985,7 +1985,7 @@ static void winqreadipospace(ScrArea *sa, void *spacedata, BWinEvent *evt)
 					
 					if( cfra!=CFRA ) {
 						CFRA= cfra;
-						update_for_newframe();
+						update_for_newframe_nodraw(1);	/* 1 = nosound */
 						force_draw_all(0); /* To make constraint sliders redraw */
 					}
 					else PIL_sleep_ms(30);
@@ -4908,8 +4908,6 @@ void force_draw_all(int header)
 	/* redraws all */
 	ScrArea *tempsa, *sa;
 
-	drawscreen();
-
 	tempsa= curarea;
 	sa= G.curscreen->areabase.first;
 	while(sa) {