Java 7 should fix these bugs. In the meantime, Jetty includes several work arounds that deal with these problems. When Jetty employs these work arounds, you see messages in your logs like the following:
JVM BUG(s) - cancelled keys 16 times
JVM BUG(s) - recreating selector 4 times, cancelled keys 32 times
JVM BUG(s) - injecting delay 8 times