In December the DotNetNuke project made a large upgrade to our issue tracker which had been stuck on an old version for the last couple of years.  We have been using Gemini from Countersoft for the last 6 years and it has served us well.  Unfortunately, earlier versions were having performance problems with the amount of issues we were tracking across all the module projects along with the Core framework.  Countersoft made a decision when moving from 2.x to 3.x to completely overhaul the security model.  If you ever had to use Gemini 2.x for a large project like ours you would have found that the task for migrating the old security settings was enormous.  We had over 40 projects each with security configuration affecting hundreds of users.  As a result of the shear amount of work involved, we avoided upgrades long past the time when an upgrade was warranted.