Bug 131000 [EFS] Drag and Drop of Folder with Spaces produces two folders in Navigator View (and other views that deal with resources)
If you grab a folder on the file system that has spaces in the name and drag it into a project in the navigator view, the folder is copied twice, once with escaped spaces (%20) and once without any escaped spaces. The folder with escaped spaces is the one with the content, the other folder has no content. This is a fairly serious bug for us because we use the CopyFilesAndFoldersOperation to do our own manipulation like this and the bug is in that class.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/wizards/datatransfer/FileStoreStructureProvider.java
logException(exception);
			return null;
		}
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.wizards.datatransfer.IImportStructureProvider#getFullPath(java.lang.Object)
	 */
	public String getFullPath(Object element) {
		return ((IFileStore) element).toURI().getRawPath();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.wizards.datatransfer.IImportStructureProvider#getLabel(java.lang.Object)
	 */
	public String getLabel(Object element) {
		return ((IFileStore) element).getName();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.wizards.datatransfer.IImportStructureProvider#isFolder(java.lang.Object)
	 */
	public boolean isFolder(Object element) {
		return ((IFileStore) element).fetchInfo().isDirectory();
	}
}