Root compiling Linux kernel for Samsung Galaxy 5 : compiled zImage doesn't work

[preetb123]

I am trying to compile Linux kernel for my Samsung Galaxy 5 with full Netfilter support:
The phone specifications are:

  Model number : GT-I5503
    Firmware version : 2.1-update1
    Baseband version : I5503DDJG5
    Kernel version : 2.6.29-perf root@SE-S605 #5
    Build number : ERE27

I downloaded **GT-I5500_OpenSource.zip** and **GT-I5503T_OpenSource.zip** from opensource.samsung.com as they contain the required kernel trees for the samsung phone, and did the following steps:

I modified the .config file for enabling full netfilter support and then for **GT-I5500_OpenSource.zip**

root@preetam:~/GT-I5500_OpenSource_Kernel/kernel# ./make_kernel.sh

    root@preetam:~/GT-I5500_OpenSource_Kernel/kernel# ARCH=arm CROSS_COMPILE=~/myandroid/prebuilt/linux-x86/toolchain/arm-eabi-4.4.0/bin/arm-eabi- make

Here i chose the toolchain from android source.

Now i got the required output, i.e.

 CHK     include/linux/compile.h
      Kernel: arch/arm/boot/Image is ready
      Kernel: arch/arm/boot/zImage is ready
      Building modules, stage 2.
      MODPOST 30 modules
    root@preetam:~/GT-I5500_OpenSource_Kernel/kernel#

I copied this zImage in the phones sdcard, and tried to flash the kernel using **SGS Kernel Flasher**. The phone rebooted, but i could still see the old kernel version in the settings... And there is no netfilter(iptables) functionality.

I followed the same steps with **GT-I5503T_OpenSource.zip**

preetam@preetam:~/GT-I5503T_OpenSource_Kernel/kernel$ ./make_kernel.sh

    root@preetam:~/GT-I5503T_OpenSource_Kernel/kernel# find . -type f -name