hi all: I found bug#537535 didn't fix complete. When I add a installation interface use db_capb escape, the interface didn't display, when I comment out this line interface is appear, but '\n' is not escape. In my program I use: db_subst test/num DEV "$dev", and $dev have '\n' in it, this '\n' didn't escape normal. I use debian-testing-amd64-CD-1.iso which generate at 2013-03-18. And I found cdebconf-udeb_0.175_amd64.udeb didn't contain debconf-escape program.
-- Best Regards, Bo Qin