Mailutils+nullmailer: sender full name

[Gertjan Klein <gklein@parvos.nl>]

I am configuring a new VPS, and decided to try nullmailer to send mail.
I don't want to receive mail on the VPS, I just want the mail the system
generates to end up in my mailbox elsewhere. This works, but the mail
from address looks like this: "gklein <gklein@parvos.nl>". This irks me.
My account has my full name configured; why isn't it used? I am testing
this as follows:

$ echo "this is a test" | mail -s Subject gklein@parvos.nl

I am unclear about which of GNU mailutils or nullmailer is responsible
for this header. I've tried various things the internet suggested; none
made any difference at all.

While this is more an annoyance than a showstopper for me, I would like
the From address to look like "My name <my@address>". Does anyone here
know which program to persuade, and how to persuade it?

Kind regards,
Gertjan.