Before doing any patching on a Solaris system, including patching during a live upgrade, make sure you have applied all of the Sun recommended patching utility patches. The basic list can be found here: http://sunsolve.sun.com/show.do?target=patchpage Look for a drop down box labeled Latest Patch Utility Patches. If you don’t see it, try logging out. You must then check each patch number in http://sunsolve.sun.com/patchfinder/ to find the latest version. The list below is accurate for Solaris 10 SPARC architecture  as of January 27, 2010.

Latest patch utilites patches list 01/26/10:

142251-01
141588-03
127884-01
125555-06
121296-01
119317-01
119254-72
121133-02
120900-04

If patching a system with zones also include the following patches:

121428-13
121430-43

Happy patching!