is there a way to drop into debug view mode after an exception?

Hi,

I know how to use Rails debugging via entering a "debugger" statement.

Question - Is there a way however to drop into the debugger mode after an exception has occurred? and effectively back back one step just prior to the exception occurs, and then you can query the variables etc. That is then a way to (a) drop from "script/server" mode to "debugger" shell, and (b) go back to the point just before the exception?

Thanks in advance