Simply put, you can have multiple versions of Java in different places.
What was happening on the not-working Macs was that the jdk versions were being used, and the Juniper vpn client won't work with them.
Recently, I was trying to get a Java applet to run in the same way on 2 i Macs and my Mac Book Air.
The applet is a simple vpn client from Juniper that lets me access a Citrix Desktop from any Mac that I can install the Citrix receiver client on so I can work on 'Company stuff' from a large screen i Mac when I'm sat at home or from my Mac Book when I'm on the road (it works fine over 3/4G).
Web applets still use the up to date, secure version 1.7 plugin.
[crarko adds: I believe Oracle has said that eventually Java will no longer support applets at all, on any platform.] A few weeks ago, a number of people started reporting having trouble with Siri.
I think the actual hint here is a reminder that if a site misbehaves, changing the user agent can be an effective troubleshooting tool.] Usually I want to open Gmail in Chrome and URLs pointing to my development server in Firefox. There is this nifty free app called Lin Castor that enables you to register your own handler for an URL.
Then I remembered the difference between 'System' Java, Java plugins, and Java development kits.
In Lin Castor (which you need to double-click twice to fully open for editing): on handle_url(args) if (|URL| of args starts with "https://mail.google.") then tell application "Google Chrome" open location |URL| of args end tell else if (|URL| of args starts with " then tell application "Firefox" open location |URL| of args end tell else tell application "Safari" open location |URL| of args end tell end return 1 end Obviously you should customize the code to suite your own specific needs.
You can validate the script right in Lin Castor before saving/activating it.
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