The bug was seen when the following is done:
# killall 1 udhpc; killall 2 udhpc
Performing a DHCP renew
state: 2 -> 5
Sending renew...
Entering released state
state: 5 -> 6 <<<<<<<<<<<<<< not calling script!!!!
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>