How can I decrypt an encrypted "Titanium Backup" backup using standard (linux) tools?

#Example:#

^{Wi-Fi serves as a practical example, many other uses may apply to the solution I'm looking for.}

If I quickly want to access backuped Wi-Fi credentials from my Linux box I know a fast way. With encrypted backups I'm currently out of luck.

That's my quick&dirty way how to do it without encryption so far:

me@local:~$ adb shell
root@android:/ # cd /sdcard/TitaniumBackup/
root@android:/sdcard/TitaniumBackup # ls W46.*gz
com.keramidas.virtual.WIFI_AP_LIST-20120622-105046.tar.gz
root@android:/sdcard/TitaniumBackup # gunzip -c W46.*gz | grep -C1 MyAccessPoint
network={

ssid="MyAccessPoint"
psk="supersecrecretpassphrase"

Some details on the company's site: http://www.titaniumtrack.com/kb/titanium-backup-kb/titanium-backup-cryptography.html