Internal Error when creating runtime+server after creating server+runtime

Following up on JBDS-4128, Preferences -> Server -> Runtime Environments -> Add and checking Create server. This seems to work now. But when I was testing it, I came across the Internal Error in that wizard and I couldn't reproduce it afterwards.

Now I have a way of reproducing the error again.
Steps:
1. Create an EAP 7.1 server using Servers –> New. Choose all the defaults - you will also create a runtime as part of this.
2. Go to Preferences -> Server -> Runtime Environments and click Add. Add a new runtime (you can use the same path as the existing one) and check Create server, so that a new server adapter should be created as well.
After you get past the new runtime page, you should see the server page where you choose the server profile. But instead, you will see just Internal Error.