DKMS make.log for dahdi-2.2.1+dfsg-1ubuntu2 for kernel 2.6.32-33-server (x86_64)
[So dkms thinks it builds for 2.6.32-33-server]
make -C /lib/modules/2.6.32-31-server/build SUBDIRS=/var/lib/dkms/dahdi/2.2.1+dfsg-1ubuntu2/build/drivers/dahdi
make[1]: Leaving directory `/usr/src/linux-headers-2.6.32-31-server'
but it actually builds with the 2.6.32-31-server headers - resulting in the symbol mismatch.
If you remove all headers except for the currently running kernel you should get a working kernel module.
Oh, I see now:
(from the make.log):
DKMS make.log for dahdi-2. 2.1+dfsg- 1ubuntu2 for kernel 2.6.32-33-server (x86_64) 2.6.32- 31-server/ build SUBDIRS= /var/lib/ dkms/dahdi/ 2.2.1+dfsg- 1ubuntu2/ build/drivers/ dahdi linux-headers- 2.6.32- 31-server'
[So dkms thinks it builds for 2.6.32-33-server]
make -C /lib/modules/
make[1]: Leaving directory `/usr/src/
but it actually builds with the 2.6.32-31-server headers - resulting in the symbol mismatch.
If you remove all headers except for the currently running kernel you should get a working kernel module.