Most people, except apparently a couple of cut-throat Wall Street companies that recently went down in flames, would hire for heart and then train for skills.  The question is, How do you identify heart?  it takes more than a resume and an interview to discover who a person really is.

So, I would think a combination of really in-depth situational interviewing and a good pre-hire assessment that measures innate personality would be the best bet for hiring for heart.