Just to be sure, I've just tested it on a squeeze box, and [found the commit that added it](http://bazaar.launchpad.net/~unattended-upgrades-developers/unattended-upgrades/trunk/revision/129).

Safe to say, it should work across the board.

```shell
# cat /etc/apt/apt.conf.d/50unattended-upgrades
// file managed by puppet
Unattended-Upgrade::Allowed-Origins {
  "${distro_id} ${distro_codename}";
  "${distro_id} ${distro_codename}-security";
};

Dpkg::Options { "--force-confold"; }

# cat /etc/debian_version
6.0.7

# unattended-upgrade --dry-run -d
Initial blacklisted packages:
Starting unattended upgrades script
Allowed origins are: ["('Debian', 'squeeze')", "('Debian', 'squeeze-security')"]
Checking: libgssapi-krb5-2 (["<Origin component:'main' archive:'oldstable' origin:'Debian' label:'Debian-Security' site:'security.debian.org' isTrusted:True>"])
Checking: libk5crypto3 (["<Origin component:'main' archive:'oldstable' origin:'Debian' label:'Debian-Security' site:'security.debian.org' isTrusted:True>"])
Checking: libkrb5-3 (["<Origin component:'main' archive:'oldstable' origin:'Debian' label:'Debian-Security' site:'security.debian.org' isTrusted:True>"])
Checking: libkrb5support0 (["<Origin component:'main' archive:'oldstable' origin:'Debian' label:'Debian-Security' site:'security.debian.org' isTrusted:True>"])
pkgs that look like they should be upgraded:
Fetched 0 B in 0s (0 B/s)
dpkg is configured not to cause conffile prompts
InstCount=0 DelCount=0 BrokenCout=0
No packages found that can be upgraded unattended
```