I needed to move some large amount of data (100Ms of rows) from a Sybase database to a MySQL database.
One of the issues I ran into is the conversion of columns of type smalldatetime, datetime and bigdatetime into a format that MySQL will readily understand.
After much struggle and after almost giving up on finding a solution that wouldn't involve some Perl massaging of the datetime data, I found a very acceptable solution.
It's doesn't meet the full ISO 8601 standard, but it's very close and for my purpose, it works perfectly.