Comment 33 for bug 292054

It would be useful if someone else could confirm this by configuring /etc/network/interfaces and comparing the start time to NetworkManager. It seems to be a different issue to the kernel regression reported by jasonwc. Alternatively the following commands will do the same if you use WEP, the modprobe stuff just ensures that the kernel drivers are started from a fresh state - skip them if you don't use an Atheros card:

ifconfig ath0 down

modprobe -r ath_pci
modprobe -r ath_rate_sample
modprobe -r ath_hal
modprobe ath_hal
modprobe ath_rate_sample
modprobe ath_pci

iwconfig ath0 mode managed
iwconfig ath0 key 1111-2222-33
iwconfig ath0 essid mywifinet
ifconfig ath0 up
dhclient