as.Date with factor argument (PR#6779)

Full_Name: J. R. M. Hosking
Version: 1.9.0
OS: WIndows 2000
Submission from: (NULL) (129.34.20.23)

f<-factor("2000-01-02")
as.Date(f)

Error in as.Date.default(f) : Don't know how to convert `x' to class "Date"

Presumably as.Date.factor(f) should have the same effect as
as.Date.character(as.character(f)), but that does not seem to be happening.