Proposed resolution (August, 2011):

Change 9.2.9.7 [dcl.spec.auto] paragraph 7 as follows:

If the list of declarators contains more than one declarator, they shall all form declarations of variables. The the type of each declared variable is determined as described above. If, and if the type deduced for the template parameter U is not the same in each deduction, the program is ill-formed. [Example:...