Yes, that is the biggest complaint so far around here. We are just closing the tickets each time we reply so if they reply it re-opens them but that does not work well in all situations.
The second most common complaint so far is that when you reply to a ticket and submit it the system posts the reply but then returns you to the same ticket instead of bringing you back to the pending tickets list. I am going to see if I can hack something in for fix that one.