[Clipart] License as www.schoolplaten.com

[Peter Mathijssen]

Hi,

I found one of my images, that i donated to openclipart, at 
http://www.schoolplaten.com/
For example: 
http://www.schoolplaten.com/nl-kleurplaat-kleurplaten-foto-pinguin-met-t-shirt-i9988.html

At the bottom of the page it says:

All images can be used for private educational, non-commercial purposes.
For all other use see Image License and/or Terms of Use 
<http://www.schoolplaten.com/copyright.php>.
Plz feel free to contact us for more information.

I contacted the webmaster and told him that i thought it was not the 
right license, because all the images on openclipart are public domain.

We had a little discussion wherein, the webmaster stated that he tought 
he didn't do anything wrong, because he gets e-mails  from people with 
questions and then tells them the images are public domain. I asked him 
why he doesn't tell that on the website right away, because he is 
restricting the use of the image in this way.

Am i right in this, of has he a right to use the image this way?

Peter