I have run into this a few times.   I soak dry posole overnight, and then add it to my sweated/sauteed vegetables, add water, and stir it regularly, and it still takes over 4 hours for the kernels to pop.   Is there a part of the process I am missing or doing wrong, or could I just be dealing with old posole?  Posole is essentially Nixtamalized Corn, or hominy. 
Use a pressure cooker. Try for example this recipe:   http://ljcny.wordpress.com/2011/09/13/chicken-pozole/  where dried hominy is cooked in a pressure cooker. 