hi, [no time to dig deeper, right now, bear with me]
when installing libglide2 which uses debconf, i gave a answer which causes the package failed to be installed, then after the batch installation, i re-run apt-get to install it, but it didn't ask the question again. i consider this is fault ui design. i.e., if the question answer has bad effects, it _should_ be asked again all the way through no need for user to do special prior setup. IMHO. regards, zw