Native Library sqljdbc_auth.dll already loaded in another classloader

I have 2 java web apps that need to connect to SQL Server Database using Windows Integrated Authentication.

The first one that is loaded works fine but the second one throws the exception:

Native Library sqljdbc_auth.dll already loaded in another classloader

The error above occurs when I place the sqljdbc_auth.dll in one of the folders:

• C:\WINDOWS\system32\
• C:\Program Files\Apache Software Foundation\Tomcat 7.0\bin\

If I place the sqljdbc_auth.dll in one of the folders below:

• /WEB-INF/lib directory of each web application
• C:\Program Files\Apache Software Foundation\Tomcat 7.0\lib\

Both apps throw the exception:

Failed to load the sqljdbc_auth.dll cause :- no sqljdbc_auth in java.library.path

I am using this code to load the driver:

Class.forName("jdbc:sqlserver://<HOST>;databaseName=<DBNAME>;integratedSecurity=true;");

How can I solve it?