Hello Heiko,
This is an upstream issue. It seems, that gspcav1 1.00.20 doesn't work with kernels > 2.6.26, as I've just read in a German forum.
The file semaphore.h is now located in /usr/src/linux-2.6.30-fbcondecor/include/linux.
So the file gspca_core.c in the gspcav1-fbcondecor package needs to be patched and "asm/semaphore.h" needs to be changed to "linux/semaphore.h".
As a workaround you can add this line to your PKGBUILD: sed -i "s:asm\/semaphore.h:linux\/semaphore.h" gspca_core.c
But you should also file a bug report to upstream, so that the gspca developers can update the software, so that it compiles with kernel 2.6.27 and above.
I tried adding that line: build() { cd $startdir/src/gspcav1-20071224 sed -i -e "s/KERNEL_VERSION = .*/KERNEL_VERSION = ${_kernver}/" Makefile sed -i "s:asm\/semaphore.h:linux\/semaphore.h" gspca_core.c <----- HERE make || return 1 #Install kernel module install -D -m644 gspca.ko $startdir/pkg/lib/modules/$_kernver/kernel/drivers/media/video/usbvideo/gspca.ko sed -i -e "s/KERNEL_VERSION='.*'/KERNEL_VERSION='${_kernver}'/" $startdir/*.install } I still recieved the same installation error messages. Forgive me if I just put it in the wrong place, but like I said before, I am new to package workings and installations, so please avoid ambiguity if it is based on the assumption of my knowledge. I started poking around in gspca_core.c, and I noticed several inclusions that look like they should be changed from the asm directory to the linux directory (I think one actually had a typo as well), but I do not know how to work around the md5sums validity checker.