jconsole/visualvm/java applications without fonts over ssh forwarding (characters displayed as boxes)

On servers which run java applications sometimes you need to run jconsole or jvisualvm.
This is typically no problem - ssh -X and you are done.

But in some rare circumstances you will get something like this:

??

Following some other sources, you end up with tweaking xorg parameter without any success. The solution is very easy:

apt-get install ttf-dejavu

And then: