Index: linux-2.6.10-ckdev/kernel/sched.c
===================================================================
--- linux-2.6.10-ckdev.orig/kernel/sched.c	2005-01-11 10:46:06.000000000 +1100
+++ linux-2.6.10-ckdev/kernel/sched.c	2005-01-11 12:03:14.746665128 +1100
@@ -567,7 +567,7 @@
 	if (iso_task(p)) {
 		rr_interval = rr_interval / 2 ? : 1;
 		if (nice < 0)
-			rr_interval += -nice;
+			rr_interval += -(nice << 1);
 	}
 	return rr_interval;
 }