When I build boxes, I do a network boot, and use a preseed file pointing to a local apt-cacher proxy.

This makes my sources.list file look like this:
deb lucid-security universe
That generally works fine, however I sometimes get a problem with downloading of release.gpg from one site or another. APT goes into an infinite loop.

The workarround is the following
echo 'Acquire::http::Pipeline-Depth "0";' >> /etc/apt/apt.conf.d/99http
Which I do as part of the install. Unfortunatly in many cases the install won't complete, because of the infinite loop.

Is there any way of using the preseed script to pass
"Acquire::http:ipeline-Depth "0";"

Something like
d-i apt-setup/acquire/http/pipeline-depth 0