Comment 2 for bug 563200

This was also a problem in 9.10 as well as 9.10 server.
It appears that the linux headers installed don't match the current linux kernel version.

After the ubuntu upgrade completed I re-run
apt-get install dahdi-dkms

This fix the problem.

I wonder if there is some sort of install order issue where the required headers are not installed until after dahdi is built.
In 9.10 server it appeared that apt-get install linux-headers was installing a version of the headers that was more recent than the running kernel. I don't know if that somehow relates to this problem.