The other topic is closed, so I'll drop my new findings here

I noticed that Google gave the following warning/error in the sitemap that was created by ZP: missing date on line 6113.

I copied and opened the sitemap in my html-editor and found this:

`
    http://www.degroeneman.nl/news/god-straft-onmiddelijk

    daily
    0.9
`

There is no date present and this news topic is the most recent added. Could this cause Google to completely refuse the sitemap?

That of course would render the sitemap invalid so that Google possibly rejects it. Does the news article actualy have a date, is it the only one without one in the sitemap and are there other errors in the log?

Normally that should of course be the date.

(Hopefully our spam friends stay away a while...)

I saved the news article again and now there was no date missing. I added the sitemap once more and Google excepted it this time. I have no idea why the date was missing in the first place.

It could have been the last updated date that was empty and was accidentally used. Maybe a bug...

Before saving that article for a second time I checked the date and it was there as it should. It just wasn't created by the sitemap.php file. I'll keep checking the sitemap to see if it happens again.

On the first saving there is of coursre not last change date. The sitemap should actually use the normal date if no last change date exists, apparently it sometimes does regardless. Will try to reproduce that (or we just make to last change date the same as the normal date for a workaround..).