Is 6/10/2003 in October or June? If the date is 1/11/2003 (regardless of whether you use little-endian or middle-endian format) does 1112003 mean 1/11/2003 or 11/1/2003, both of which are valid in both systems?

Pay heed to the advice to use YYYY-MM-DD format. Not only does it lend itself to convenient sorting as another Monk noted, it's also unambiguous and an international standard. If you have a single-digit day or month, pad it with zero using sprintf or one of the other solutions presented here.