Comment 1 for bug 775206

It's not a typo as such. The actual text is:

</footnote>. We'll also assume that your kernel version &kernelversion;. Make sure you are in the directory to where you want to
unpack the kernel sources, extract them using <userinput>tar xjf /usr/src/linux-source-&kernelversion;.tar.bz2</userinput>

Not sure why it is calling one version down. I figured this might actually be something I'd know how to fix but alas, no.