I'm going to post the whole process in case something went wrong with the last CF file.
(Do not install Clockworkmod from market, if you have it installed, Remove it)
1. Download this CF file: http://www.mediafire.com/?1o650o0zcnd7c4n
2. Unzip the file "CF-Root-XW_NEE_JVH-v3.2-CWM3RFS.tar"to desktop/CF-ROOT/ (create the folder CF-ROOT on your desktop and put the file in it).
3. SHIFT+Right click and open Odin as admin, I guess you have it downloaded already or else download the latest version here: http://www.mediafire.com/?i27nn2say2808j8
4. Turn your phone off. Wait for vibration to confirm complete switch off.
5. Now you want to boot your phone in Download Mode: Press and hold “VolumeDOWN + HOME key + POWER button” together.
6. Connect the phone to PC. Make sure that Odin has recognized your phone.
7. Now you want to click on the "PDA" button in Odin and select the "CF-Root-XW_NEE_JVH-v3.2-CWM3RFS.tar" that you Unzip'd to desktop/CF-ROOT/ folder.
8. Make sure that you do
NOT have any “.pit” file selected in the “PIT” box, and make sure “Repartition” button is NOT checked.
9. Leave the “Auto Reboot” and the “F. Reset Time” buttons checked.
10. Just to make sure double check Step 7, 8 and 9.
11. Click on the "Start" button in Odin tool.
12. After the install is complete the phone should reboot itself.
13. Install
Superuser from android market.
Now:
Reboot the phone into recovery by:
1. Turn off phone.
2. Press and hold until Galaxy S logo appears: VolumeUP+HOME+POWER
Now try do a nandroid backup.