Bug 23968 Abusive check on task tags
2.1M1 Java UI ensures that task tags are valid Java identifiers. Why is it so ? JDT/Core supports any type of tags. In particular, "TODO:" should work fine, and was one of the mentionned tags on the original feature request.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/CompilerPreferencePage.java
public String getValue(int index) {
			return fValues[index];
		}		
		
		public int getSelection(String value) {
			for (int i= 0; i < fValues.length; i++) {
				if (value.equals(fValues[i])) {
					return i;
				}
			}
			throw new IllegalArgumentException();
		}
	}
	
	private Hashtable fWorkingValues;
	private ArrayList fCheckBoxes;
	private ArrayList fComboBoxes;
	private ArrayList fTextBoxes;
	
	private SelectionListener fSelectionListener;
	private ModifyListener fTextModifyListener;
	
	private ArrayList fComplianceControls;
	IStatus fComplianceStatus, fMaxNumberProblemsStatus, fResourceFilterStatus, fTaskTagsStatus;
	public CompilerPreferencePage() {
		setPreferenceStore(JavaPlugin.getDefault().getPreferenceStore());
		setDescription(JavaUIMessages.getString("CompilerPreferencePage.description")); 
	
		fWorkingValues= JavaCore.getOptions();
		fWorkingValues.put(INTR_DEFAULT_COMPLIANCE, getCurrentCompliance());