Although Java ES 5 is support on all versions of Solaris 9 and Solaris 10 on SPARC and x86 platforms, Sun recommends that you use the following updates:
Solaris 9: Update 7 (9/04) or newer
Solaris 10 SPARC: Update 1 (1/06) or newer
Solaris 10 x86: Update 2 (6/06) or newer