The Debian project has been working in removing non-free firmware from the Linux kernel shipped with Debian for the past two release cycles. At the time of the releases of Debian 4.0 “Etch” [1] and 5.0 “Lenny” [2], however, it was not yet possible to ship Linux kernels stripped of all non-free firmware bits. Back then we had to acknowledge that freedom issues concerning Linux firmware were not completely sorted out [3][4].
1: http://www.debian.org/releases/etch/
2: http://www.debian.org/releases/lenny/
3: http://www.debian.org/vote/2006/vote_007
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