This from the manual for your computer:"
-on passwordIf you forget the power-on password and need assistance to reset it a password reset fee will be charged and your computer may need to be send in for depot service for password reset" WOW they are serious about their passwords. The manual is available at http://www.retrevo.com/support/Sony-VGC-...
Pulling out the battery is CMOS/RTC battery is usually the only way though. If you attempt to pull the RTC battery, make sure that you have all other sources of power disconnected (AC power and notebook battery). Keep the RTC battery out for about 30 minutes before reassembling the laptop. The result should be that he BIOS has been reset to the defaults settings, which includes no password protection.
The only othr way that I can think of right now is to go here and try this software http://www.cgsecurity.org/wiki/CmosPwd It worked for me on a few occasions ..... good luck and let us know how it is going.