check return DM_SETITEMPOSITION

git-svn-id: http://farmanager.googlecode.com/svn/trunk@11477 ea59307d-ff68-5b67-5a21-acd59c66a581
check return DM_SETITEMPOSITION

git-svn-id: http://farmanager.googlecode.com/svn/trunk@11478 ea59307d-ff68-5b67-5a21-acd59c66a581