There aren't many rules that you need to worry about here on the Ranch, but one that we take very seriously regards the use of proper names. Please take a look at the JavaRanch Naming Policy and adjust your display name to match it.
In particular, your display name must be a first and a last name separated by a space character, and must not be obviously fictitious.
Whether you can do this will probably be determined by which RDBMS you are using. For example, it is possible to use NTLM authentication with SQL Server (assuming your driver is jTDS). Which database are you using?
Well, I've never heard of anyone doing it, but I understand you can configure an external authentication source for an Oracle database, with could be an Active Directory repository. But that's the database itself -you'd also need a driver that support NTLM and I don;t think the drivers supplied with Oracle do (you'd better check this - I'm not 100% sure). You might have to buy a third party driver such as DataDirect.