ON STOCK ROM ...
1- you dont need to relock the bootloader ..
2- download voodoo rootkeeper .. (from market) and run the program and click protect root.
3- you will need your original recovery that you changed to CWM ..
example: if you had 1.28.415.9 and you installed CWM then you need recovery.img for 1.28.415.9 .
install the stock recovery from http://forum.xda-developers.com/show...5#post24738635
4-install recovery.img from fastboot ..
5-boot into phone and OTA update the one x to 1.29.xxx .
6-after update is done just open rootkeeper and click restore root ,,
a big thanks for xda members and im happy to help ...