You can get these ear plugs that have a small vent in them. the vent is small enough water stays out but you can still equalize (according to the way I understand it). I know these ear plugs were used by a free diver in setting a world record, and they are also sold at Vortex Springs. If you go to their web page you can see them and they explain them. They tell you that only the vented plugs can used for scuba, and they claim that equalizing is easier.
http://www.proplugs.com
http://www.proplugs.com
