Bug 28510 java build path inconsistency [build path]
20021216 select rt.jar in the package explorer open properties it allows you to set the javadoc location but for source attachment you are sent somewhere else it's inconsistent - on the java build path they both look sort of the same (they sit under the same node in the tree)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/buildpaths/BuildPathsBlock.java
if (!isChecked) {
					fClassPathList.setCheckedWithoutUpdate(currElement, true);
				}
			} else {
				currElement.setExported(isChecked);
			}
			entries[i]= currElement.getClasspathEntry();
			if (currElement.isMissing()) {
				nEntriesMissing++;
				if (entryMissing == null) {
					entryMissing= currElement;
				}
			}
		}
				
		if (nEntriesMissing > 0) {
			if (nEntriesMissing == 1) {
				fClassPathStatus.setWarning(NewWizardMessages.getFormattedString("BuildPathsBlock.warning.EntryMissing", entryMissing.getPath().toString())); 
			} else {
				fClassPathStatus.setWarning(NewWizardMessages.getFormattedString("BuildPathsBlock.warning.EntriesMissing", String.valueOf(nEntriesMissing))); 
			}
		}
				
/*		if (fCurrJProject.hasClasspathCycle(entries)) {
			fClassPathStatus.setWarning(NewWizardMessages.getString("BuildPathsBlock.warning.CycleInClassPath")); 
		}
*/		
		updateBuildPathStatus();
	}
	/**