can you attach a screenshot of the avast message
Sucuri http://sitecheck.sucuri.net/results/www.athlocosmos.gr
quttera say suspicious http://quttera.com/detailed_report/www.athlocosmos.gr suspicious here - /plugins/content/jw_ts/jw_ts/includes/js/behaviour.min.js
urlquery http://urlquery.net/report.php?id=8901984
zulu http://zulu.zscaler.com/submission/show/619bb2b34fd96af11545c4c2bede9814-1390214079