code: public WTab addTab(final WComponent content, final String tabName, final TabMode mode, final char accessKey) {
  		return addTab(new WTab(content, tabName, mode, accessKey));
  	}
docs: Adds a tab to the tab set.
  
  @param content the tab set content.
  @param tabName the tab name.
  @param mode the tab mode.
  @param accessKey the access key used to activate the tab.
  @return the tab which was added to the tab set.