The Lenovo ThinkServer Management Module features remote console capabilities which gives you full screen, keyboard and mouse control of the Lenovo server. It's like sitting right in front of the server and allows you to do some fancy things like configure the BIOS or install an operating system remotely.
While connected to a remote site via IPSec VPN, I was able to login to the web interface without a problem. I clicked the "Launch Java KVM Client" and downloaded the familiar JNLP file "viewer.jnlp(192.168.0.jnlp". Opening the file displays the Java loading screen, and a prompt to tell me it's downloading and starting the application - great. The "Connecting to KVM Server" prompt appears, but immediately after, a "Login failed" dialog box which ended the application.
After doing some Google'ing I saw other people experiencing the same issue but with no solution. I made sure there was no firewall policy blocking the VPN connection from accessing the default Java KVM port of 2068, and that there were enough available sessions (with a max of 4 sessions, 0 were active). I opened my favourite packet analyzer and tried to determine where the connection was failing, and I noticed that my username was being sent as 1234567890 and my password was 0987654321.
Opening the "viewer.jnlp(192.168.0.jnlp" in a text editor showed the offending lines below:
Simply editing the user and passwd values to what I used to login to the ThinkServer Management Module, saving the file and re-running the new, altered "viewer.jnlp(192.168.0.jnlp" file let me connect with no problems.
It seems as though the downloaded JNLP file was just a generic file that was ignoring my session credentials, and I expect it will be fixed in a firmware update, but for now I have my modified file which works as expected.