It seems Busting has been revamped to now be harder, but there is no official confirmation. Many people have posted bug reports about failing 20 times or more in a row and each have been answered by staff in a similar fashion..
“Busting appears to have been made harder. ~asdalavista”
“Yes busting appears to be made harder, you’ll have to get used to it. ~asdalavista
“pssst, maybe its not a bug, but just harder to bust people from now on… ~Drmark“
Though people have had much trouble with busting upon every try, it is still possible to bust. So busting certainly is not broken. However there has been no official anouncement as to whether the jail has been revamped or not. All we have is speculation from various staff members.
“There have been some small changes which you will only notice if the person you are busting is a much higher level than you or if they are in for a very long amount of time. People who have high dexterity shouldn’t notice a difference.
Would be glad to hear feedback in the forums.