You don’t have to wait on the firmware for you country, just download the Spanish one.
It contains Most of the language.(FOR International version unlock version only.)
If you want to install it ,here is a guide:
1. Download Zip Spanish firmware file and extract it.
2. Download Odin and run it (Odin3 v3.07)
3. If u don’t have kies, install it. but don’t run it.
4. Enter your s2′s download mode by pressing power button + home key + volume down key for few seconds.
5. After entering download mode press volume up key to continue.
6. Connect your mobile to phone via data cable.
7. Then click PDA button (in odin) and choose I9100XWLS8_I9100XXLS8_I9100FOPLS3_HOME.tar file.
8. click start button. wait for few minutes until ODIN says PASS.
Note: Update your phone at your risk.
Watch out below video for Samsung Galaxy SII with Android 4.1.