Trouble creating a discussion list

I tried to create my first discussion list last night.
But for all variations of input that I’ve tried I keep
seeing this error message – and I don’t think the
list gets created:

Can’t call method “param” on an undefined value at /usr/local/lib/site_perl/Ndn/Dhwebpanel/Mail/ line 164.

I’ve entered details like this:

listname circlec-talk
owner email
password …

I clicked Yes for convenience email addresses.
Am I doing something wrong to create a discussion list?