Error message

• Notice: Trying to get property of non-object in aggregator_page_rss() (line 358 of /home/chroch1/kefren.be/modules/aggregator/aggregator.pages.inc).
• Notice: Trying to get property of non-object in theme_aggregator_page_rss() (line 407 of /home/chroch1/kefren.be/modules/aggregator/aggregator.pages.inc).
• Notice: Trying to get property of non-object in theme_aggregator_page_rss() (line 408 of /home/chroch1/kefren.be/modules/aggregator/aggregator.pages.inc).