Is 10.5 vunerable to the Flashback.G Trojan?

Question

If 10.5 is up to date, is it vunerable to the Flashback.G Trojan that was reported on 2/24?  All of the news items about this speak only of 10.6 or 10.7.  They imply that if OS X is up to date, then there are no worries. 

Answer 1

Few malicious titles actually exist for Mac OS X, and those that do almost entirely rely upon duping users to install software that pretends to be legitimate, however A new version of an existing Trojan Horse posing as a legitimate Flash Player installer (named “Flashback.A” by a security firm) is designed to disable updates to the default Mac OS X anti-malware protection system, potentially leaving the system open to the manual installation of other malware without any system warnings. In order to prevent a potential infection with “Flashback” Trojans, Mac users are advised to obtain their copy of Adobe Flash Player directly from Adobe’s official website and to disable the "Open 'safe' files after downloading" option in Apple's Safari browser to avoid automatically running files downloaded from the Internet.
http://www.appleinsider.com/articles/11/10/19/fake_adobe_flash_malware_seeks_to_ disable_mac_os_x_anti_malware_protection.html
UPDATE regarding the Flashback Trojan:
http://blog.intego.com/new-flashback-trojan-horse-variant-uses-novel-delivery -method-to-infect-macs/
and also: http://blog.intego.com/flashback-mac-trojan-horse-infections-increasing-with -new-variant/