I saw Knuth talk at Kepler's Bookstore in Menlo Park some years ago. Someone asked him which language was better Java or C++. He replied: "Whichever has the better debugger".
No, they aren't. With Java you can change code while the application is running and it will be hot-swapped after you have recompiled it.
I learned about this feature when playing a bit in Eclipse, forgot to kill the program between edits, and got a warning that the recompiled class couldn't be hot-swapped because its signature changed. And then I sat there in awe; I can just dream about this functioning reliably with C++.
"Supports", "works" and "is usable" are three totally different things. I doubt that E&C is truly usable since even much simpler things -- for example, data breakpoints when debugging native+managed code -- is unsupported in VS2010. (Needed exactly that today.) E&C is disabled also for C# as soon as you turn on native-code debugging.