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http://jtds.sourceforge.net/faq.html

Windows Single Sign On (SSO) Authentication using

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NTLM

Just leave the username and password blank and jTDS uses the ntlmauth.dll that is placed in the distributions \libswt\win32 folder and logs on with the logged in user credentials.

For further information search for NTML NTLM in the jTDS FAQ. E.g. you can also specify the domain option:

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