solução
Button register not always work [Thu Oct 11 14:32:16 2012] [error] [client 89.70.196.48] PHP Notice: Trying to get property of non-object in .../sklep/cache/smarty/compile/56f33365973edda1462e913c286bdec322292f24.file.authentication.tpl.php on line 112, referer:
change line 166 in ./themes/default/authentication.tpl
with <input type="button" id="SubmitCreate" name="SubmitCreate" class="button_large" value="
{ls='Create your account'}" /> on <input type="submit" id="SubmitCreate" name="SubmitCreate" class="button_large" value="{ls='Create your account'}
" />