eclipse suddenly crashed wile adding new software

see the summary...

If I add the JAVA Language:
Cannot complete the install because of a conflicting dependency.
  Software being installed: Eclipse Java Development Tools 3.5.2.r352_v20100108-7r88FEwFI0WTuoBl0iaG0tyhfZH6 (org.eclipse.jdt.feature.group 3.5.2.r352_v20100108-7r88FEwFI0WTuoBl0iaG0tyhfZH6)
  Software currently installed: Eclipse Platform 3.5.2 (Eclipse Platform 3.5.2)
  Only one of the following can be installed at once:
    Eclipse Java Development Tools 3.5.1.r351_v20090810-0600-7r88FEoFI0WTo6Az-1qFRHm37ChJ (org.eclipse.jdt.feature.jar 3.5.1.r351_v20090810-0600-7r88FEoFI0WTo6Az-1qFRHm37ChJ)
    Eclipse Java Development Tools 3.5.2.r352_v20100108-7r88FEwFH4SRsd9dz0fZ6z-rwffZ (org.eclipse.jdt.feature.jar 3.5.2.r352_v20100108-7r88FEwFH4SRsd9dz0fZ6z-rwffZ)
    Eclipse Java Development Tools 3.5.2.r352_v20100108-7r88FEwFI0WTuoBl0iaG0tyhfZH6 (org.eclipse.jdt.feature.jar 3.5.2.r352_v20100108-7r88FEwFI0WTuoBl0iaG0tyhfZH6)
  Cannot satisfy dependency:
    From: Eclipse Platform 3.5.2 (Eclipse Platform 3.5.2)
    To: org.eclipse.jdt.feature.jar [3.5.2.r352_v20100108-7r88FEwFH4SRsd9dz0fZ6z-rwffZ]
  Cannot satisfy dependency:
    From: Eclipse Java Development Tools 3.5.2.r352_v20100108-7r88FEwFI0WTuoBl0iaG0tyhfZH6 (org.eclipse.jdt.feature.group 3.5.2.r352_v20100108-7r88FEwFI0WTuoBl0iaG0tyhfZH6)
    To: org.eclipse.jdt.feature.jar [3.5.2.r352_v20100108-7r88FEwFI0WTuoBl0iaG0tyhfZH6]

If I add the CPP Language than it starts and suddenly:
An error occurred while installing the items
  session context was:(profile=PlatformProfile, phase=org.eclipse.equinox.internal.provisional.p2.engine.phases.Install, operand=null --> [R]org.eclipse.cvs 1.0.400.v201002111343, action=org.eclipse.equinox.internal.p2.touchpoint.eclipse.actions.InstallBundleAction).
  The artifact file for osgi.bundle,org.eclipse.cvs,1.0.400.v201002111343 was not found.

But I cant replicate the crash till now I'll go on

I use:
Ubuntu 10.04.1 LTS
Release: 10.04

Eclipse:
 Installiert: (keine)
  Kandidat: 3.5.2-2ubuntu4.2
  Versions-Tabelle:
     3.5.2-2ubuntu4.2 0
        500 http://de.archive.ubuntu.com/ubuntu/ lucid-updates/universe Packages
     3.5.2-2ubuntu4 0
        500 http://de.archive.ubuntu.com/ubuntu/ lucid/universe Packages

I hope I can help you
greetings Odonata