This solution applies to OS X clients connecting to Barracuda SSL VPNs, all firmware versions.
First, ensure you have the latest version of Java installed (1.7u11 at the time of writing).
Then open a Terminal prompt and type in:
# sudo vi /System/Library/CoreServices/CoreTypes.bundle/Contents/Resources/XProtect.meta.plist
In that file, change the Java version number from 188.8.131.52 to 184.108.40.206 and save the file.
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