Check Software Upate! Apple has released a couple of updates to Java, this being the first for Snow Leopard and the sixth for Leopard, bringing the latest versions of Java for OS X (SE6 and SE5) to versions 1.6.0_17 and 1.5.0_22, respectively. These updates addresses security issues with applets gaining elevated privileges and invalid certificates being treated as valid.
The 10.6 update is 78MB and can be downloaded from here: http://support.apple.com/kb/DL972
The 10.5 updater is 122MB and can be downloaded from here: http://support.apple.com/kb/DL971
Being a small security update we do not see any obvious source of problems with these updates, but if you experience any incompatibilities, please let us know either in the comments section, on the CNET forums, or by emailing us.