OK I use now Sun 5 Java and I get when I click to update:
Requested operation cannot be performed because it would invalidate the
current configuration. See details for more information.
Platform configuration has been modified outside this program. A restart
is recommended.
But it is a clean and fresh sudo eclipse install without anything else
done in Eclipse respect. I even removed all Eclipse folders (Krusader
root) and also the deb packages before I  did install via  sudo apt-get
again....
Will now try Sun 1.4 and report on that. The blackdown 1.4 cause teh
same result.
If you need some logs etc pls advise.

OK now 5 removed 1.4 installed via synaptic. aptitude reinstall eclipse
Computer restart. and the same....

---------------------------
eclipse -check
searching for compatible vm...
  testing /usr/lib/jvm/java-gcj...found
!SESSION 2007-02-02 09:40:14.189
-----------------------------------------------
eclipse.buildId=M20060921-0945
java.fullversion=GNU libgcj 4.1.2 20061115 (prerelease) (Ubuntu
4.1.1-20ubuntu1)
BootLoader constants: OS=linux, ARCH=x86_64, WS=gtk, NL=en_US
Framework arguments:  -check
Command-line arguments:  -os linux -ws gtk -arch x86_64 -check

!ENTRY org.eclipse.osgi 4 0 2007-02-02 09:40:14.863
!MESSAGE Error reading configuration: cannot create temporary file
!STACK 0
java.io.IOException: cannot create temporary file
   at java.io.File.createTempFile(libgcj.so.70)
   at
org.eclipse.osgi.storagemanager.StorageManager.initializeInstanceFile(StorageManager.java:187)
   at
org.eclipse.osgi.storagemanager.StorageManager.open(StorageManager.java:700)
   at
org.eclipse.osgi.internal.baseadaptor.BaseStorage.initFileManager(BaseStorage.java:152)
   at
org.eclipse.osgi.internal.baseadaptor.BaseStorage.initialize(BaseStorage.java:129)
   at
org.eclipse.osgi.baseadaptor.BaseAdaptor.initializeStorage(BaseAdaptor.java:124)
   at
org.eclipse.osgi.framework.internal.core.Framework.initialize(Framework.java:138)
   at
org.eclipse.osgi.framework.internal.core.Framework.<init>(Framework.java:112)
   at
org.eclipse.osgi.framework.internal.core.OSGi.createFramework(OSGi.java:90)
   at org.eclipse.osgi.framework.internal.core.OSGi.<init>(OSGi.java:31)
   at
org.eclipse.core.runtime.adaptor.EclipseStarter.startup(EclipseStarter.java:286)
   at
org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:173)
   at java.lang.reflect.Method.invoke(libgcj.so.70)
   at org.eclipse.core.launcher.Main.invokeFramework(Main.java:336)
   at org.eclipse.core.launcher.Main.basicRun(Main.java:280)
   at org.eclipse.core.launcher.Main.run(Main.java:977)
   at org.eclipse.core.launcher.Main.main(Main.java:952)

--------------------------
now I checked that gtk (command line)
There is a

libswt3.2-gtk-java 3.2.1-2ubuntu1
libswt3.2-gtk-jni 3.2.1-2ubuntu1
libswt3.2-gtk-gci 3.2.1-2ubuntu1

trying to remove libswt3.2-gtk-java causes that Eclispe is removed
completely...
After reinstalling of Eclipse the same. libswt3.2-gtk-java is back and
You can start to read above, Update not possible. Nice deadlock.
I should repeat that I use a clean amd64 feisty herd 2 disk. No old
ubuntu or kubuntu remains on my HD. Complete reformatted. Only the
feisty  repositories. Upgraded once the day via upgrade manager.
Whats next???

Áron Sisak wrote:
> Do you have the Sun JVM installed? I guess Eclipse is working (better) with that.
> I think I also have various plugins installed and they seem to work flawlessly.
>
>