from the manual of patent examining procedure:

http://www.uspto.gov/web/offices/pac/mpep/mpep_e8r7_2200.pdf

2260.01 Dependent Claims [R-2]

If ** >an unamended base patent claim (i.e., a

claim appearing in the reexamination as it appears in

the patent)< has been rejected or canceled, any claim

which is directly or indirectly dependent thereon

should be confirmed or allowed if the dependent

claim is otherwise allowable. The dependent claim

should not be objected to or rejected merely because it

depends on a rejected or canceled patent claim. No

requirement should be made for rewriting the dependent claim in independent form. As the original patent

claim numbers are not changed in a reexamination

proceeding, the content of the canceled base claim

would remain in the printed patent and would be

available to be read as a part of the confirmed or

allowed dependent claim.

If a new base claim (a base claim other than a base

claim appearing in the patent) has been canceled in a

reexamination proceeding, a claim which depends

thereon should be rejected as *>indefinite<. If a new

base claim >or an amended patent claim< is rejected,

a claim dependent thereon should be objected to if it

is otherwise patentable and a requirement made for

rewriting the dependent claim in independent form