extract-vmlinux script doesn't work with ARM kernels

The extract-vmlinux script that is included in the linux-headers-(version) package doesn't work with ARM vmlinuz kernels. The script fails with the following message: "Cannot find vmlinux."

Looking at the script everything seems to execute correctly, but after stripping off the header and running the result through gunzip an elf file is expected. The result is not recognized as an elf file, so the script fails.

/usr/src/linux-headers-$(uname -r)/scripts/extract-vmlinux /boot/vmlinuz-$(uname -r) > /tmp/vmlinux
extract-vmlinux: Cannot find vmlinux.

The scripts works with an x86 kernel.