Proposed resolution (October, 2009):

Change 9.2.2 [dcl.stc] paragraph 4 as follows:

The thread_local specifier indicates that the named entity has thread storage duration (6.7.6.3 [basic.stc.thread]). It shall be applied only to the names of objects or references of namespace scope, to the names of objects or references of or block scope that also specify extern or static, and to the names of static data members. It specifies that the named object or reference has thread storage duration (6.7.6.3 [basic.stc.thread]). When thread_local is applied to a variable of block scope the storage-class-specifier static is implied if it does not appear explicitly.