libglide2: debconf didn't ask question even for failed answer

[zhaoway <zw@debian.org>]

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