I did what you suggested(deleted the simlock.ta) and tried flashing..no luck, still the same error. screen shots attached.
Just to update, I managed to flash the phone with docomo ROM using the ftf file(2-3 weeks back I had flashed the phone with the xperia S ROM which took me to this mess). While flashing with docomo rom now I "excluded baseband" in the flashtool. So now I have the original docomo version installed but the baseband version is blank("unknown") in the "about phone" page. rest everything is there like the model number, android version, kernel version and build number.
The problem that I still have now since I flashed it with the Xperia S rom, is that there is no IMEI still ;o(( I have the IMEI number from the box. Any suggestions to bring back the IMEI and teh baseband versions back?
Look forward to a solution!! I am running out of time with the warranty!!!