we have an '05 odyssey ex-l. is it possible to program it so that when you place the vehicle in park all the doors unlock? I have that feature available on my '06 ridgeline, so I thought there might be a way to program the odyssey as well.

Nope. You cannot program them. That feature was an addition to 2007 model year.

For 2005 and 2006 only the Touring had progammable locks.

http://www.odyclub.com/forums/showthread.php?s=&threadid=31927&highlight=auto+lock

http://www.odyclub.com/forums/showthread.php?s=&threadid=46688&highlight=automatic+and+locks