I am not at liberty to disclose the technology used unfortunately, otherwise I would have given more information in my previous post.

While rails may be quick to develop with and may be great for prototypes it is not something that is ready for the prime time. The cost to get up to speed in Java was negligible compared to the end result, in that we are now able to have less time spent trying to debug problems because of Ruby not functioning correctly or having to be restarted (we had several tasks that took some database crunching in which ruby would sometimes fall over, or just take up all of the available memory thereby starving other processes and eventually being killed by the oom killer leaving parts of our database in an inconsistent state).