Groovy Debugging problem --- cannot evaluate local variables referenced from inside of closures

First mentioned on the mailing list:

http://groovy.329449.n5.nabble.com/Groovy-Eclipse-Debugging-issue-Watch-expression-doesn-t-work-tp4864139p4870464.html

Trying to debug this script:

def current = 1
next = 1
10.times {
	print current + ' '
	newCurrent = next
	next = next + current
	current = newCurrent
}
println ''

Set a breakpoint inside the closure and try to evaluate next. It is an error. The problem is that we are not properly looking up variables defined in the outer scope of a closure.