Comment 8 for bug 374105

$ sudo find /lib/modules/2.6.32-2*
/lib/modules/2.6.32-20-generic
/lib/modules/2.6.32-20-generic/modules.alias
/lib/modules/2.6.32-20-generic/modules.symbols
/lib/modules/2.6.32-20-generic/modules.ofmap
/lib/modules/2.6.32-20-generic/modules.isapnpmap
/lib/modules/2.6.32-20-generic/modules.usbmap
/lib/modules/2.6.32-20-generic/modules.inputmap
/lib/modules/2.6.32-20-generic/modules.ieee1394map
/lib/modules/2.6.32-20-generic/modules.symbols.bin
/lib/modules/2.6.32-20-generic/modules.pcimap
/lib/modules/2.6.32-20-generic/modules.seriomap
/lib/modules/2.6.32-20-generic/updates
/lib/modules/2.6.32-20-generic/updates/drivers
/lib/modules/2.6.32-20-generic/updates/drivers/net
/lib/modules/2.6.32-20-generic/updates/drivers/net/wireless
/lib/modules/2.6.32-20-generic/updates/drivers/net/wireless/ath
/lib/modules/2.6.32-20-generic/updates/drivers/net/wireless/ath/ath9k
/lib/modules/2.6.32-20-generic/updates/drivers/net/wireless/ath/ath9k/ath9k_hw.ko
/lib/modules/2.6.32-20-generic/updates/drivers/net/wireless/ath/ath9k/ath9k.ko
/lib/modules/2.6.32-20-generic/updates/drivers/net/wireless/ath/ath9k/ath9k_common.ko
/lib/modules/2.6.32-20-generic/updates/drivers/net/wireless/ath/ath.ko
/lib/modules/2.6.32-20-generic/updates/compat
/lib/modules/2.6.32-20-generic/updates/compat/compat_firmware_class.ko
/lib/modules/2.6.32-20-generic/updates/compat/compat.ko
/lib/modules/2.6.32-20-generic/updates/net
/lib/modules/2.6.32-20-generic/updates/net/mac80211
/lib/modules/2.6.32-20-generic/updates/net/mac80211/mac80211.ko
/lib/modules/2.6.32-20-generic/updates/net/wireless
/lib/modules/2.6.32-20-generic/updates/net/wireless/cfg80211.ko
/lib/modules/2.6.32-20-generic/modules.dep
/lib/modules/2.6.32-20-generic/modules.alias.bin
/lib/modules/2.6.32-20-generic/modules.dep.bin
/lib/modules/2.6.32-20-generic/modules.ccwmap
/lib/modules/2.6.32-21-generic
/lib/modules/2.6.32-21-generic/updates
/lib/modules/2.6.32-21-generic/updates/drivers
/lib/modules/2.6.32-21-generic/updates/drivers/net
/lib/modules/2.6.32-21-generic/updates/drivers/net/wireless
/lib/modules/2.6.32-21-generic/updates/drivers/net/wireless/ath
/lib/modules/2.6.32-21-generic/updates/drivers/net/wireless/ath/ath9k
/lib/modules/2.6.32-21-generic/updates/drivers/net/wireless/ath/ath9k/ath9k_hw.ko
/lib/modules/2.6.32-21-generic/updates/drivers/net/wireless/ath/ath9k/ath9k.ko
/lib/modules/2.6.32-21-generic/updates/drivers/net/wireless/ath/ath9k/ath9k_common.ko
/lib/modules/2.6.32-21-generic/updates/drivers/net/wireless/ath/ath.ko
/lib/modules/2.6.32-21-generic/updates/compat
/lib/modules/2.6.32-21-generic/updates/compat/compat_firmware_class.ko
/lib/modules/2.6.32-21-generic/updates/compat/compat.ko
/lib/modules/2.6.32-21-generic/updates/net
/lib/modules/2.6.32-21-generic/updates/net/mac80211
/lib/modules/2.6.32-21-generic/updates/net/mac80211/mac80211.ko
/lib/modules/2.6.32-21-generic/updates/net/wireless
/lib/modules/2.6.32-21-generic/updates/net/wireless/cfg80211.ko

The 2.6.32-2* kernels apparently left some stuff behind due to linux-backports-modules-wireless packages as previously mentioned.