senseless mount message

After

sudo mount -t cifs -vvv -o credentials=~/.smbcredentials //192.168.1.2/austausch /media/austausch

The message:

domain=mydomain
Credential formatted incorrectly: (null)
mount.cifs kernel mount options: ip=192.168.1.2,unc=\\192.168.1.2\austausch,user=myuser,,domain=mydomain,pass=********

appears. Is this an info, warning or error message?

The .smbcredentials looks like:

username=myuser
password=mypassword
domain=mydomain

But it mounts the remote content. I think there should not be this empty argument.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: cifs-utils 2:6.4-1ubuntu1.1
ProcVersionSignature: Ubuntu 4.4.0-81.104-generic 4.4.67
Uname: Linux 4.4.0-81-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.1-0ubuntu2.6
Architecture: amd64
CurrentDesktop: Unity
Date: Thu Jun 29 13:34:43 2017
SourcePackage: cifs-utils
UpgradeStatus: No upgrade log present (probably fresh install)