… Ted Stevens is neither the chairman nor the ranking member of the Senate Appropriations Subcommittee on Defense:

Information on Senate Republican Conference Rules
Indictment or Conviction of Committee Chair/Ranking Member
“In the event of an indictment for a felony, the chair/ranking member or elected member of the leadership shall step down until the case is resolved. Upon conviction, the chair/ranking member would automatically be replaced.”
[Rule V (D), Senate Republican Conference Rules]
Action Taken Today:
Senator Stevens, in compliance with Rule V (D), has stepped down as Ranking Member of the Senate Commerce Committee and the Appropriations Subcommittee on Defense.

(Statement from McConnell’s office.)