I have just discovered that I had the wrong information in the above post concerning the time allowed to exchange a drivers licence. Please note that this applies only to non EU licences. Instead of 6 months as I originally stated, a driver must exchange his licence within three months of obtaining residence in Portugal. However, the non EU driver may drive in Portugal for up to 6 months after his entry in Portugal as long as he is not a resident.
For this error, I apologise with all my heart. I have now edited the original post to give the correct information.