Hi, I'm looking at https://issues.apache.org/jira/browse/WICKET-5311 and the SCM history of AbstractSingleSelectChoice class and I've noticed:
commit e3bd9d3d8a1103b0c69fe6301be7e95630ff1066 Author: Eelco Hillenius <ehillen...@apache.org> Date: Tue Apr 10 04:29:44 2007 +0000 rolled back deprecation of nullValid git-svn-id: https://svn.apache.org/repos/asf/incubator/wicket/branches/wicket-1.x@52701613f79535-47bb-0310-9956-ffa450edef68 which reverts a change where setNullValid(boolean nullValid) did setRequired(!nullValid). I cannot find any earlier commit or a ticket that explains the reason for the change neither in Git, nor at http://svn.apache.org/viewvc, nor at https://fisheye6.atlassian.com/browse/wicket/trunk/jdk-1.4/wicket/src/main/java/org/apache/wicket/markup/html/form/AbstractSingleSelectChoice.java . Does someone remember the discussion about this change ?