, SecurityFocus 2003-11-06
Software developers on Wednesday detected and thwarted a hacker's scheme to submerge a slick backdoor in the next version of the Linux kernel, but security experts say the abortive caper proves that extremely subtle source code tampering is more than just the stuff of paranoid speculation.

Penguinisto
...and they had access to the Windows source trees for upcoming products (like XP ferinstance) for months on end.
Here BTW is Microsoft's admission of it:
http://news.com.com/2100-1001_3-247719.html
So - you were saying? ;)
/P...
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