From Bugzilla Helper:
User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.4.2)
Gecko/20040301

Description of problem:
In the CDT when moving the cursor over a C/C++ keyword, the following
traceback is generated:

Exception in thread "Text Viewer Hover Presenter" java.lang.Error: Not
implemented
  at java.util.regex.Pattern.compile(java.lang.String)
(/lib/ssa/libgcj.so.4.0.0)
  at java.lang.String.split(java.lang.String) (/lib/ssa/libgcj.so.4.0.0)
  at org.eclipse.cdt.internal.ui.CTextHover.initialize()
(/usr/lib/eclipse/plugins/org.eclipse.cdt.ui_1.2.0/libcdtui.so)
  at org.eclipse.cdt.internal.ui.CTextHoverContributorManager$1.run()
(/usr/lib/eclipse/plugins/org.eclipse.cdt.ui_1.2.0/libcdtui.so)
  at
org.eclipse.core.internal.runtime.InternalPlatform.run(org.eclipse.core.runtime.ISafeRunnable)
(/usr/lib/eclipse/plugins/org.eclipse.core.runtime_2.1.1/libruntime.so)
  at
org.eclipse.core.runtime.Platform.run(org.eclipse.core.runtime.ISafeRunnable)
(/usr/lib/eclipse/plugins/org.eclipse.core.runtime_2.1.1/libruntime.so)
  at
org.eclipse.cdt.internal.ui.CTextHoverContributorManager.loadExtensions()
(/usr/lib/eclipse/plugins/org.eclipse.cdt.ui_1.2.0/libcdtui.so)
  at
org.eclipse.cdt.internal.ui.CTextHoverContributorManager.getFunctionInfo(java.lang.String)
(/usr/lib/eclipse/plugins/org.eclipse.cdt.ui_1.2.0/libcdtui.so)
  at
org.eclipse.cdt.internal.ui.editor.DefaultCEditorTextHover.getHoverInfo(org.eclipse.jface.text.ITextViewer,
org.eclipse.jface.text.IRegion)
(/usr/lib/eclipse/plugins/org.eclipse.cdt.ui_1.2.0/libcdtui.so)
  at
org.eclipse.cdt.internal.ui.editor.CEditorTextHoverDispatcher.getHoverInfo(org.eclipse.jface.text.ITextViewer,
org.eclipse.jface.text.IRegion)
(/usr/lib/eclipse/plugins/org.eclipse.cdt.ui_1.2.0/libcdtui.so)
  at org.eclipse.jface.text.TextViewerHoverManager$2.run()
(/usr/lib/eclipse/plugins/org.eclipse.jface.text_2.1.0/libjfacetext.so)
  at _Jv_ThreadRun(java.lang.Thread) (/lib/ssa/libgcj.so.4.0.0)
  at GC_start_routine (/lib/ssa/libgcj.so.4.0.0)
  at __clone (/lib/tls/libc-2.3.2.so)


Version-Release number of selected component (if applicable):
eclipse-2.1.2-3.i386.rpm

How reproducible:
Always

Steps to Reproduce:
1. bring up Eclipse CDT
2. move cursor over a keyword
3.
    

Actual Results:  see description

Expected Results:  information on the keyword should be displayed

Additional info:

There is a known patch for this that can be applied.  It will be
applied and tested to see if it fixes this version/release.