Connecting to ATEN KVM-over-IP from a modern environment

We have several KN4132v and KN2140v appliances connected to multiple servers in our lab. These are multi-thousand dollar devices that I would be hard-pressed to justify throwing away.

Unfortunately, the only way we have for connecting to them is through an ATEN CC2000 system that only supports Internet Explorer running an old version of Java. It stopped working on my Windows laptop at some point, and I have not been able to get it working again.

Is there any way to connect to these things without using a Java applet, preferably from Linux?

EDIT: I resorted to downloading a VirtualBox image from Microsoft, and installing Java 7 from the Java Download Archive. Also had to set Java security to low. I feel dirty.