I believe pimp my wii can do that... never used the program myself though as it has the nasty tendency to update all IOS to the latest version even if you're on an older system menu (If you're on System Menu 4.1, the latest official IOS 60 that the system menu uses is a stub)
Use ModMii guide to download IOS 236 Installer, MMM, Rev20 249(56) and 250(38).
Then load HBC and run IOS 236 installer - skip step 2.
Next run MMM, reload IOS 236, go WAD Manager and install Rev20 249 and 250 wads. (you will get error if MMM wont load ios 236).
let me know if worked.