Need help with HTML:RedirBA-inf [Trj]

Hello,
one of our customers claims he has HTML:RedirBA-inf [Trj] on his site. And hist AVAST detects it. Can you please help us with any information how to detect it and delete? All founded information is related to tools for Home PC based on Windows. But how can it be removed from website? Or maybe it is false-positive? Mentioned web-site is http://ipij.ru

sucuri report
http://sitecheck.sucuri.net/results/ipij.ru/

urlvoid
http://www.urlvoid.com/scan/ipij.ru/

hosted on same IP
http://www.urlvoid.com/ip/78.140.185.138/

virustotal
https://www.virustotal.com/url/a769d4a38c730c0fe1d92d68d4b85ad0d542aa540bba31d120f66d5677dd096d/analysis/1359020447/

cleanMX
http://support.clean-mx.de/clean-mx/viruses?id=8639178

virustotal scan of file listed at cleanMX
https://www.virustotal.com/file/baa0a32ec340564bfe77c9688cb64610bb297f79cd2f8bdefea7b9b347fb1ce3/analysis/

Dear Pondus,

All of these websites shows the same thing - site is infected. We know it already.
Can you please tell us how the website can be cured? Any virus details, so we can delete dangerous HTML code? At the moment we don’t understand what to do with it. Thank you.

you may try Sucuri, they are experts on this…not free. http://sucuri.net/signup