This site indicates trojan.osx.boonana.a is related to Koobface, spreads through social networking sites (be careful where you click) and is cross-platform because of Java. Whether the Windows definitions will be able to pick up on the Macs is unknown (since the Macs will get the Windows definitions by default, but this may be a new variant), so it's definitely recommended to submit any suspicious files so they can be analyzed.
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