A support request filed on LiveJournal suggest users contact WordPress support.
http://www.livejournal.com/support/see_request.bml?id=1288068
If you do not wish to click the link, the text is here for your convenience:
"I'm sorry for the delay in following up your request. Yes, the error message you report indicates that your WordPress imports are timing out because of high traffic at LiveJournal. However, there is nothing that LiveJournal users can do to make third-party tools better able to access their journals. You may wish to contact WordPress' support department again and ask them if they can adjust the way in which their import tool works so that LiveJournal does not reject its requests".
Blog url: http://panscloset.wordpress.com/