I was trying to install kernel 2.6.25 on fedora 14(2.6.35.6-45.fc14.i686).
But it is giving the following error at step 'make install'

ERROR: modinfo: could not find module mperf
ERROR: modinfo: could not find module snd_hda_codec_realtek
ERROR: modinfo: could not find module snd_hda_codec
ERROR: modinfo: could not find module drm_kms_helper

However the following files are created under /boot

initramfs-2.6.25.img
vmlinuz-2.6.25
System.map-2.6.25

also /boot/grub/grub.conf and /boot/grub/menu.lst are updated properly.
but when i tried to boot the kernel 2.6.25 it is showing the following error and hanging

"FATAL:kernel too old
[0.897645] Kernel panic-not syncing:Attempted to kill init "

What will be the reason for this problem?

I built the kernel with glibc version-2.12.90, gcc version 4.5.1, binutils version 2.20.51.

Is it caused by the tools i used for compiling the 2.6.25 kernel ?

2.6.25 is circa 2008. Many changes have been made since then. The last 2.6 kernel was 2.6.35 and the latest stable release is 3.7.2. Maybe you have an EFI BIOS? Do you know that 2.6.25 supports your current hardware?

I think it was the problem of using newer version of build tools for building a relatively old kernel.
I installed fedora 8 in the same machine and was able to successfully compile, install and boot 2.6.19 kernel.