[Zodb-checkins] SVN: ZODB/trunk/NEWS.txt Merge part of rev 29784 from 3.3 branch.

[Tim Peters]

Log message for revision 29785:
  Merge part of rev 29784 from 3.3 branch.
  
  This is news about ZEO protocol changes.  The promised
  update of README.txt will have to be rewritten from
  scratch for 3.4 (the new text in 3.3's README.txt isn't
  quite right for the 3.4 release).
  

Changed:
  U   ZODB/trunk/NEWS.txt

-=-
Modified: ZODB/trunk/NEWS.txt
===================================================================
--- ZODB/trunk/NEWS.txt	2005-04-01 16:20:43 UTC (rev 29784)
+++ ZODB/trunk/NEWS.txt	2005-04-01 16:23:55 UTC (rev 29785)
@@ -151,7 +151,18 @@
 depending on platform, and should suffer far fewer (if any) intermittent
 "timed out waiting for storage to connect" failures.
 
+ZEO protocol and compatibility
+------------------------------
 
+ZODB 3.3 introduced multiversion concurrency control (MVCC), which required
+changes to the ZEO protocol.  The first 3.3 release should have increased
+the internal ZEO protocol version number (used by ZEO protocol negotiation
+when a client connects), but neglected to.  This has been repaired.
+
+Compatibility between pre-3.3 and post-3.3 ZEO clients and servers remains
+very limited.  See the newly updated ``Compatibility`` section in
+``README.txt`` for details.
+
 FileStorage
 -----------