I did this mod on my stock rooted L900 and added auto rotation. Worked great.
I'm running stock rooted which means odexed.
First thing was deodexing SecLauncher2.apk using Univeral Deodexer
After that I followed the OP instructions, but I really wanted the launcher to auto rotate as well. So I went to res/values/integers.xml
and under resources I changed screenOrientation from 1 to 3
-> <integer name="config_screenOrientation">3</integer>
Changing the cell values for landscape was really common sense after changing the portrait values. Icon labels get a little truncated in landscape mode, but with some tweaks I am sure I could get it right.