Proxy Server for NT 4.0

Hello,

We use NT 4.0 and we need to install a proxy server that integrates with NT USERS DATABASE.

I tried WINGATE but I am looking for more products that Integrate with NT 4.0 USERS DATABASE.

Do you know any other proxy server product?

PS: Microsoft Proxy Server 2.0 is not available any more.

Thank you in advance.