[SR-Users] kamailio 3.1.4

[Ryan d'Eon]

Hello,
I'm trying to support a kamailio install, and they are having a crashing issue. I'm not looking for detailed help on the problem, I just noticed one thing I'd like to check up on here:
kamailio 3.1.4 (the version they are running) isn't available for download anymore, though quite a few other old versions are. Are there known bugs? Meaning, should I be worried about this, and go back with the recommendation to upgrade? 
If so, which is the ideal upgrade path? 3.1.5? 3.1.6? 
Thanks for any help.
Ryan