By adding the bean to the OptimisticLockException one is able to print a better error message to the user.

Untested yet, but easy enough that it should work:

Index: ../ebean/src/com/avaje/ebean/server/core/PersistRequestBean.java
===================================================================
--- ../ebean/src/com/avaje/ebean/server/core/PersistRequestBean.java (revision 210)
+++ ../ebean/src/com/avaje/ebean/server/core/PersistRequestBean.java Wed Apr 08 09:54:00 CEST 2009
@@ -117,7 +116,7 @@
public void checkRowCount(int rowCount) throws SQLException {
if (rowCount != 1) {
String m = Message.msg("persist.conc2", "" + rowCount);
- throw new OptimisticLockException(m);
+ throw new OptimisticLockException(m, null, getBean());
}
}