I have finally solved this problem.
First I accessed my machine with a Fedora 9 live usb.
I noticed that kernel installed in my upgraded Fedora 10 machine was still that of fedora 9. I have no idea why.
I downloaded Fedora 10 kerenel : kernel-22.214.171.124-117.fc10.i686.rpm and tried to install it with rpm.
But it gave an error that a new and latest kernel in already installed.
I used --oldpackage option with rpm and forced install it.
Then I used mkinitrd -v to create initial ramdisk image.
Rest was a simple change in Grub configuration to use the new vmlinuz-126.96.36.199-117.fc10.i686 to boot.