Gnus number of unread articles change when switching from 22.2 to 23

[Klaus Zeitler]

Hello,
I'm currently switching often between 22.2 and the CVS version
(The CVS version is sometimes unbearably slow, but I haven't found enough
time to investigate this).
Every time I switch from 22.2 to 23 and use gnus in emacs 23, gnus shows
lots of unread articles in the group buffer.
Now if I read them or use catch up, then use gnus in version 22.2 and
finally use the CVS version again, the articles are shown as unread again.
Is there an incompatible change between the 2 versions?
Where should I start investigate this?

Thanks
Klaus

-- 
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|  Klaus Zeitler      Alcatel-Lucent               |
|  Email:             address@hidden  |
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Have you noticed that all you need to grow healthy,
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