which Anti-Virus Program could you recommend ??

Hi list, i want to scan a Samba-File Server for Viruses. At this time i am testing F-Secure AV for Linux an it runs fine, but a Server licence costs 300 Euro. (Workstation 90 Euro - but i think i need Server-Licence ?) For me its important to have good update - support to always get the newest signatures (ok, what is newest) It would be nice if you could tell me your choises and experiences, thx a lot - Andreas (box: Suse 7.3 / Samba / mostly Win9x clients)