A possible workaround for this issue is to reinstall Safari 5.0.5 parallel to new Safari 5.1. I did this by recovering the older Safari version from TM backup.
Another way is described in this hint: http://hints.macworld.com/article.php?story=20110722154439693
This browser does not use the Cocoa Java Plug-In.
1) Make sure that the JVM 1.4.1 or later is installed
2) Check that this browser supports Java for Cocoa (such as Safari)
With several Mac users to support the dutch Amstelveen Council would like to be able to offer a solution other then the workarounds. These prove to be overstretching the capabilities of the average user.
However another question remains: is the solution forthcoming from Apple or is this a Java problem?
Thanks for your tip. Unfortunately, it did not seem to resolve the problem for me.
Perhaps I am reading your web page wrong but it seems to say that the file to install in the Library is: JavaPluginCocoa.bundle. That file already exists in my Library.
I downloaded the file you suggested but that file is named JavaPluginCocoa.plugin. I installed this as you suggested but it had no affect.
What am I doing wrong?
The file should be called .bundle rather than .plugin. You can rename the file or download it again as I have just renamed the file in the zip archive. Sorry about that. You can check what plugins you have loaded using
Installed Plug-ins"inside Safari. Make sure it has loaded JavaPluginCocoa.bundle.
If it has but you still get the error let me know - I don't have access to a mac for a few weeks to test it out again but it shouldn't be too hard ot work out whats wrong.