An update:
I ran across this helpful article:
http://weblogs.java.net/blog/guruwons/archive/2006/09/understanding_t.html
Essentially, the EntityManager is caching without refreshing the results. I tried what the article suggests, and manually refreshed the Reservation object, but it didn't work. I also tried using the hint() functionality provided by TopLink, but that didn't work either. By disabling caching altogether, it seems to work every time now.
Is there a way to avoid disabling caching? I think there's a solution that would be better than this -
Thanks-
Steven
[Message sent by forum member 'steven_landers']
http://forums.java.net/jive/thread.jspa?messageID=475281