this is what this site i found has on the subject
"Powerhouse" was an airplane "marked for destruction"
(17 September 2006) According to Ken Miller, "Powerhouse" was a plane marked for death by the Japanese Air Force. Tokyo Rose said so, on the air. Here is the story as relayed to me by Ruth, Ken Miller's significant other. Ruth writes:
Supposedly Ken Miller and about 6 other men, including Theo, were in the tent area and listening to the shortwave radio early one evening in New Guinea. Ken said he didn't often do this, but he was there when Tokyo Rose came on and said, "For you pilots in the South Pacific, the B-25 with the dog chewing the Japanese flag has been marked for destruction by the Japanese air force." They all laughed and Theo said, "Let them come."
the link for more info on the plane
http://home.mchsi.com/~anderson.kevin/roy_powerhouse.html-Gambit