Installation media: ubuntu-10.04-desktop-i386.iso

I tried a lot of different boot parameters, but either the installer ignored the preseed configuration, or it boot itself directly as LiveCD.

An example of the boot parameters I've tried:

auto url=http://mydomain.com/path/preseed.cfg boot=casper only-ubiquity initrd=/casper/initrd.lz quiet splash --

If I remove only-ubiquity, it boots as a LiveCD. If I remove boot=casper, it won't boot. If I add vga=normal locale=en_US console-setup/layoutcode=us console-setup/ask_detect=false interface=auto, it still can't do automatic install. If I remove auto, it's the same.

What is the correct boot parameters for launching such an installation?

From the apache log of the server hosting preseed.cfg, I see that the installer has no problems fetching the preseed file. My preseed file is almost identical to the one at https://help.ubuntu.com/10.04/installation-guide/example-preseed.txt. Moreover, I have run debconf-set-selections -c preseed.cfg to ensure that the preseed file is correct.