Kernel 2.6 on Tao x86_64

I want to install Asterisk (VOIP PBX) on a x86_64 Tao U3 box. The modules 
that come with Asterisk give me a headache therefore I was thinking of 
installing a stock 2.6 kernel.

Does anyone have experience with running a 2.6 stock kernel on Tao x86_64?

I'm running into 2 problems:

First and major, on every boot the kernel complains about my root= 
statement in grub.conf. A normal grub.conf entry looks like this:
kernel /vmlinuz-2.4.21-27.301.EC ro root=LABEL=/

But I am not using initrd (compiled the SCSI driver in the kernel) and 
when booting the LABEL= statement didn't work. So I tried
kernel /vmlinuz-2.6.10 root=/dev/sda2
but when the box is booting it hangs with an error :
cannot open root device "sda2"

Second some modules are not compiling. I get loads of unresolved symbols 
errors on the ipv4 and ipv6 modules:
depmod: *** Unresolved symbols in 
/lib/modules/2.6.10/kernel/net/ipv6/netfilter/ip6t_hl.ko
depmod: ip6t_unregister_match
depmod: ip6t_register_match
depmod: *** Unresolved symbols in
/lib/modules/2.6.10/kernel/net/ipv6/netfilter/ip6t_ipv6header.ko
depmod: ip6t_unregister_match
depmod: ip6t_register_match
depmod: ip6t_ext_hdr
depmod: *** Unresolved symbols in
/lib/modules/2.6.10/kernel/net/ipv6/netfilter/ip6t_length.ko
depmod: ip6t_unregister_match
depmod: ip6t_register_match
depmod: *** Unresolved symbols in
/lib/modules/2.6.10/kernel/net/ipv6/netfilter/ip6t_limit.ko

and many many more