[xwiki-users] MySQL Error "invalid use of group function" in Statistics application

Hello, I just migrated from XWiki 1.1 to 1.2.2. Migration was ok and everything works fine, except the Statistics application. It shows unrecorded stats but there are some. There seems to be an error in an SQL request (miss group by ?), either database was not correctly migrated, or MySQL version is not compatible ? Of course, stats are activated in xwiki.cfg. Here's the error log when trying to display the most viewed pages : [.../Stats/MostViewedPages] [http-80-Processor18] WARN util.JDBCExceptionReporter - SQL Error: 1111, SQLState: HY000 [.../Stats/MostViewedPages] [http-80-Processor18] ERROR util.JDBCExceptionReporter - Invalid use of group function (2 times) I use : mysql Ver 14.7 Distrib 4.1.20, for redhat-linux-gnu (i386) using readline 4.3 java version "1.5.0_11" Thanks for help, Jeremie