For some reason ZTE change the ident string of the kernel, for example, from the dmesg on a ZTE Blade2:

Self-built kernel:
<6>[01-01 00:00:00.000000] [0: swapper]Initializing cgroup subsys cpu
<5>[01-01 00:00:00.000000] [0: swapper]Linux version 2.6.35.7-perf ([email protected]) (gcc version 4.4.3 (GCC) ) #7 PREEMPT Fri Dec 2 15:54:44 PST 2011
<4>[01-01 00:00:00.000000] [0: swapper]CPU: ARMv6-compatible processor [4117b365] revision 5 (ARMv6TEJ), cr=00c5387f

Stock kernel:
<6>[01-01 00:00:00.000000] [0: swapper]Initializing cgroup subsys cpu
<5>[01-01 00:00:00.000000] [0: swapper]Linux version 2.6.35.7-perf+ (xueyibing@zhangchun-desktop) (gcc version 4.4.3 (GCC) ) #1 PREEMPT Fri Nov 18 09:58:25 HKT 2011
<4>[01-01 00:00:00.000000] [0: swapper]CPU: ARMv6-compatible processor [4117b365] revision 5 (ARMv6TEJ), cr=00c5387f


Note the extra +

In my experience if you boot any ZTE device with a self built kernel the RIL wont work because it thinks it's linked against a different kernel, you need to either hax0r the RIL library or the kernel...