Have your try connecting your iPad to other public wifi hotspots such as McDonald, Cafe's...and see whether you have problem like you stated at your office? If you have no problem with those wifi hotspots then there's no problem with your iPad, it's probably your company configuration that prevent your Mac address or ip to log into the Internet. You should refer to your network administrator to do the job then.
If the problem still the same with those public hotspots, try update to the latest FW 4.3.3(ATM) to try again and if it's still fail to retify the problem.....send it back for warranty.