Version 4 of package Mysql Driver is available on squeakmap. This version supports the newer client authentication protocol in Mysql 4.1/5.x. I've marked it Beta for now - feedback is appreciated.
-Alan Reider
From the release notes:
* Compatible with new Mysql 4.1/5x authentication and resultset changes. * Should also work with 4.1/5x with old (short) passwords. * May still work with Mysql 4.0 and below and Squeak 3.7 and below. * Fixed float conversion not to use '+', eg '3.041234e+23' is N/G in Squeak 3.8. * Added new Integer type used in Mysql 5.x (as mentioned by Boingo) * Test suites upgraded, eg factored connectionSpec 4 ez changing. * Test suite passed on Squeak 3.8 w/ Mysql 5.0.38 on Ubuntu. * Requires Cryptography package (as previously)