BLOODCLOT  I'm in the same boat, my G5 2.5 dual ppc was placed on the obsolete list yesterday. Now I have to miss the snow leopard boat, also won't run the latest java update. SOOOO NOT COOL.  
(Version Update 4)

PHILIP GONIA  Worked out how to get Java running within Safari.

In Java Preferences I selected Run Applets within Java Browser.

Java however is still broken within FireFox.

Also found this info about Java update 3.

[ http://mactip.blogspot.com/2007/11/safari-crash-firefox-crash-applet-crash.html ]

Found this very interesting. Looks as though Java 6 on MAC OS X is broken. Oops!

[http://lists.apple.com/archives/java-dev/2007/Oct/msg00367.html]

What is described here is the same as what I am seeing but after installing on a new installation of MAC OS X "Leopard" (10.5.7)

Java 5 is all that will run!  
(Version Update 3)

MACFOOL  Those having problems subsequent to these updates should Safe Boot and run Repair Permissions in Disk Utility.  
(Version Update 4)

LEPPE  This is what you need to run Java in other browsers then Safari:

http://www.macupdate.com/info.php/id/16262/java-embedding-plugin

Greets

Leppe

Here is some info from the project site:

The Java Embedding Plugin is a utility that allows other web browsers than Apple's Safari to use the most recent versions of Java on Mac OS X. When used together with an updated version of Mozilla's MRJ Plugin Carbon (included in this distribution), the Java Embedding Plugin's functionality is currently available to recent versions of Firefox, Seamonkey and Camino. But in principle any web browser could use one of the Java Embedding Plugin's two APIs to add support for Java 1.4.2, J2SE 5.0 and (where available) Java SE 6.  
(Version Update 4)

EAN  If your PPC can run OS X, then feel free to install whatever version of Java you like!  
(Version Update 3)

GERMANO60  @EAN: maybe you didn't got the point. If you own a PPC with Mac OS X you can not install Java 1.6 simply because this is available only for Intel-based Macs. So, with a PPC you can not install "whatever Java you want", you simply can't install a Java version that you "must" have to run some programs.

And that's unfair for owners of PPC-based Macs.  
(Version Update 3)

WERFBLAU  @EAN: There‘s no 1.6 for PPC-Macs.

Unfortunately it‘s true: More and more Java-Apps require 1.6, so the PPC-Macs are out of the business.

Apple’s attitude does not only affect the Java-Platform, but also their own products like iLive - some functionality is only available for Intel-Macs!

Btw: I’m currently evaluating Linux - there are distributions for PPCs, too.  
(Version Update 3)

ESPIRIDION  Thanks for the replies and for clarifying my post to EAN.

WERFBLAU, I recently installed OpenSUSE http://www.opensuse.org/en/ but removed it after a couple of days. Installation was relatively easy. Yellow Dog was another option I considered. One of the Java programs I'm interested in is not ported to Linux, though. But check them out, they may work for you.  
(Version Update 3)

MINER  PPC Linux 9 (at least the most recent Fedora, which is the biggest supported PPC-distro I think) is worse;

I cannot get ThinkFree Office installed at all, no matter what I try. Also some java-web apps do not work.

For PPC, OS X is still the most versatile, even with these limitations.  
(Version Update 3)

HELMO HASS  i choose to say bye bye to apple.. well not really.. just to their machines.. for instance, and frankly im happy with that, having osx is nice, running it from a PC its priceless!

GG STEVE.. btw, ppc should have been discontinued in two years, NOT NOW, according to apple policy..

At least now i've a real mac lol, with no limitations, and capable of running any hardware i need.. Please guys lets do us a GREAT FAVOUR, move to linux!

Apple is dead.   
(Version Update 3)

DRAGONFIST  Actually Java 6 isn't even available for all Intel Macs. I'm running a first Generation MBP that has the Core Duo Processor...no 64Bit...no Java 6...problems here you come ;-)  
(Version Update 3)

JOELLEVIN  Good luck when Snow Leopard comes out...  
(Version Update 3)

D9  Is anyone here aware of why Apple has not ported Java 1.6 to PPC?

Assumptions that it motivates upgrades to Intel Macs or is Apple's apathy towards Java are just that, assumptions. Just like I could assume that it's a severe technical issue with 1.6 working properly with Mac OS X on PPC.

/  
(Version Update 3)

STAR-AFFINITY  HELMO HASS

”Apple is dead”

No, PPC is dead. :P ;)

(At least on the Macs for now)  
(Version Update 3)

WERFBLAU  ESPIRIDION, I started to evaluate Yellow Dog - it looks nice, but they are even behind Apple for Java.

JOELLEVIN: I‘ll not jump into the Snow-Leopard - Apple managed it to get .0 releases at least as buggy as another commercial OS, so I‘ll wait and look on the PPC-Macs. I used to buy Family Licenses.

D9: It took Apple more than 2 years to get Java 6 to the Intel Macs...

I hope somebody from Apple reads this — the song is no longer "Apple is the best“.  
(Version Update 3)

VEGGIEDUDE  I do not see why Apple should be faulted for no longer fully supporting PPC 5 years after moving to Intel.   
(Version Update 3)

ESPIRIDION  VEGGIEDUDE, Apple's Java support also affects Intel users, but for PPC users it is just worse.

In addition, Apple typically cares too little about backwards compatibility. This Java situation is just a current example. Recent switchers may not have experienced this yet.  
(Version Update 3)

GERMANO60  @Veggydude: Apple moved to Intel for the public at the beginning of 2006. We're now in 2009, so it's not 5 years, it's 3 years.

When Apple moved from 68K to PPC, the transition took definitely longer. Do you really think that the HUGE Apple's installed base of PPC has fully or almost fully moved to Intel in these last 3 years? I'm not so sure about it. But Apple seems not to care.

My iMac G5 is 4 year old now, it's running smoothly and perfectly, I don't see any reason to buy a brand new machine just because Apple decided purposedly on an early shutdown of maintenance for the old platform.   
(Version Update 3)

MIKURO  Regarding Linux, I think PPC users are excluded from Sun's Java, but IBM offers a JRE for PPC. Installing it is not always easy, but it's doable. I've installed it on PPC Debian with a bit of jumping through hoops.

I don't have detailed instructions on hand, but here's a quick tip for anyone searching: changing the name of the file you download to match that of an older version may be necessary. While following instructions I found in various places online, I found that one of the required tools only worked with "known" version numbers (meaning only versions older than the tool's release), even though newer versions were compatible. Changing the file name was the key to getting it to work.  
(Version Update 3)

PDD  I had the same issue with Quantrix Modeler and found a solution by modifying the instruction found here: http://www.jetbrains.net/devnet/message/5240115#5240115

In the Terminal type (all on one line):

cp /System/Library/Frameworks/JavaVM.framework/Resources/MacOS/JavaApplicationStub64 /Applications/Quantrix Modeler.app/Contents/MacOS/JavaApplicationStub

Quantrix Modeler now loads!  
(Version Update 4)

I(POWER)MAC  there's nothing to fix:

- by one side: "This release of J2SE 5.0 and J2SE 1.4.2 supports all Intel and PowerPC-based Macs. Java SE 6 is available on 64-bit, Intel-based Macs only." (Description);

- by other side: "64-bit Intel Mac (Core 2 Duo or Xeon) for Java SE 6" (Requirements).

Both the above sentences say the same thing.  
(Version Update 2)

EGINZBURG  It also introduces important fixes to http://www.allianceformarriage.org/. I am very happy.  
(Version Release 6)

DAVID.ACORD  Tip: Ignore bigoted retorts like the one above.  
(Version Update 2)