I listened to an archived brewing with style in the brewing network for German wise and Jamil said he ferments his hefe's at 62 deg. My basement temp lately had been around 66-68 ish, and I know the fermentation will raise the temp a fee degrees. I may have to do the wet towel thing since I do not have a chest freezer empty.
In my experience, Jamil is right on. Pitching the proper amount of yeast and fermenting cool makes a fantastic hefe!