It is always good to keep an eye on your data sources if you don’t want to miss out on new versions. Like the Global Administrative Areas database (GADM), which published version 2 of their data set earlier this year (I thought about revisiting their site after reading this post). A fairly relevant update with updated boundaries for e.g., Sudan. and with level two administrative boundaries now available for most countries.
The files are available as shapefile, ESRI personal or file geodatase, Google earth .kmz file or R spatial polygon dataframe. If only they would make it available in spatialite format.. (I know, it is easy enough to import shapefiles into a Spatialite database, I am just being lazy).