[asterisk-users] channel variables not kept

[Paradise Dove]

hi,
i'm using asterisk 1.4.21.2, and i use channel variables in my agi scripts.
the problem is that some variables (and maybe all, not sure) like
ANSWEREDTIME does not kept if the caller hangs up.
my agi script continues to run after caller/callee hangup but the
variables are not set properly if callers hangs up.
is there anything i should to to avoid this or it's a bug.

thanks,
paradise dove