I install latest GAPPS and Velvet - After that, Google now work perfectly for my i9250/maguro MIUI 2.8.17/JB
1. Reboot in CWM
2. Wipe cache & wipe dalvik
3. Install latest GAPPS: http://goo.im/gapps/gapps-jb-20120726-signed.zip
4. Again, wipe cache & wipe dalvik
5. reboot
6. install...