Error 07 with 404 at comments

[Poll]

I get an error (07) if I would add a comment, that´s contains spam.

I write something stupid like this...
comment = gfdgfdg
name = gfdgfdg
URL = gfdgfdg
mail = gfdgfdg

The return messages is this:

Not Found
The comment could not be accepted because it got flagged as SPAM by our anti-SPAM measures. (ERR: 07).

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request. 
Click here to go BACK

I have found some think like this with the search here. But only with (ERR: 01) and (ERR: 03). But what means 07?
<TOKEN> is activated and inserted.

[Dennis+]

Err 7 is invalid email. If you fill something in it will have to be a valid email address. For your testing you can leave it empty.

[Poll]

Okay, thank you very much Denis!