Multiple pbuilders setting from pbuilder User's Manual doesn't seem to work

Hi,

Multiple pbuilders setting from pbuilder User's Manual doesn't seem to work for me.

The FAQ section 8 from pbuilder User's Manual (http://www.red-bean.com/doc/pbuilder/pbuilder-doc.html#ENVVARDISTRIBUTIONSWITCH) describes briefly a way to setup and use multiple pbuilder setups by creating a pbuilderrc configuration in home path ($HOME/.pbuilderrc) and using the variable "DIST" when running pbuilder or pdebuild.

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First, setup $HOME/.pbuilderrc to look like:

if [ -n "${DIST}" ]; then
        BASETGZ="`dirname $BASETGZ`/$DIST-base.tgz"
        DISTRIBUTION="$DIST"
        BUILDRESULT="/var/cache/pbuilder/$DIST/result/"
        APTCACHE="/var/cache/pbuilder/$DIST/aptcache/"
fi
Then, whenever you wish to use pbuilder for a particular distro, assign a value to "DIST" that is one of the distros available for Debian or any Debian based distro you happen to be running (i.e. whatever is found under /usr/lib/debootstrap/scripts).

Here's some examples on running pbuilder or pdebuild:

DIST=gutsy sudo pbuilder create

DIST=sid sudo pbuilder create --mirror http://http.us.debian.org/debian
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That's exactly what I did.

$ cat ~/.pbuilderrc
if [ -n "${DIST}" ]; then
        BASETGZ="`dirname $BASETGZ`/$DIST-base.tgz"
        DISTRIBUTION="$DIST"
        BUILDRESULT="/var/cache/pbuilder/$DIST/result/"
        APTCACHE="/var/cache/pbuilder/$DIST/aptcache/"
fi

DIST=oldstable

$ DIST=$DIST sudo pbuilder create --distribution $DIST --mirror http://http.us.debian.org/debian --debootstrapopts "--keyring=/usr/share/keyrings/debian-archive-keyring.gpg"
...
I: unmounting proc filesystem
I: creating base tarball [/var/cache/pbuilder/base.tgz]
I: cleaning the build env
I: removing directory /var/cache/pbuilder/build//20348 and its subdirectories

I.e., shouldn't the created base tarball following the BASETGZ="`dirname $BASETGZ`/$DIST-base.tgz" convention?

Thanks