I believe that your failure was caused by some problem with the SQL Server driver when trying to use Integrated Authentication (also called Integrated Security).
from the MS website (emphasis mine)
The JDBC driver supports the use of type 2 integrated authentication on Windows operating systems using the IntegratedSecurity connection string property. To use integrated authentication, copy the sqljdbc_auth.dll file to a directory on the Windows system path on the computer on which the JDBC driver is installed.
The sqljdbc_auth.dll files are installed in the following location: \ Sqljdbc _ \\ Auth \
Note If you are using the 32-bit Java Virtual Machine (JVM), use the sqljdbc_auth.dll file in the x86 folder, even if the operating system is x64 version. If you are using a 64-bit JVM on an x64 processor, use the sqljdbc_auth.dll file in the x64 folder. If you are using a 64-bit JVM on an IA-64 processor, use the sqljdbc_auth.dll file in the IA64 folder .
Alternatively, you can set the java.libary.path system property to specify the sqljdbc_auth.dll directory.
For example, if the JDBC driver is installed in the default directory, you can specify the location of the DLL using the following virtual machine (VM) argument when starting the Java application: -Djava.library.path = C: \ Microsoft SQL Server 2005 JDBC driver \ sqljdbc_ \ enu \ auth \ x86
{end quote from MS website}
PS: To disable integrated authentication / security, change the IntegratedSecurity flag in the JDBC connection string to false (i.e.: integratedSecurity = false)
Additional Information:
http://msdn.microsoft.com/en-us/library/ms378428(v=sql.90).aspx