As the bug is still unresolved (and the ticket has been reopened), I've attached a .diff to be applied to the .orig.tar.gz, so that dpkg-buildpackage can be used to build the package which in turn will be named "libapache2-mod-security".
The diff is basically just libapache-mod-security_2.5.11-1~bpo50+1.diff.gz plus the needed modification to change the package name. Just in case the attachment gets lost, I've put the diff and a mini howto on: http://nerdbynature.de/bits/BTS-516540/ Thanks, Christian. -- BOFH excuse #180: ether leak
libapache2-mod-security_2.5.11-1~bpo50+2.diff.gz
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