ClamXav is a free virus checker for Mac OS X. It uses the tried, tested and very popular ClamAV open source antivirus engine as a back end.
Inlcudes engine version 0.75-1
Please note: This is the final version which will work with OS X 10.2. Any problems encountered with 0.8.7c were fixed in later releases and this version is now unsupported.
If you like using ClamXav you can make a donation
from here.