You need to install Solstice AdminSuite 2.3 patch number 104468-06 or any subsequent revision of this patch before you add OS services to your server. You will find the patch and installation instructions at http://access1.sun.com/private-cgi/patch2html?README.104468-06.
If you are using Solstice AdminSuite with a patched Solaris release in which it is inadvisable or impossible to remove all the patches, then you will need to have the following file to add OS services:
2.5.1: MU3, MU4, and MU5
2.6: MU1 and MU2
With this workaround, Solstice AdminSuite is unable to track all the patches in a system. Use admclientpatch to add or remove patches to or from the system.
If you are unable to obtain the patch from access1.sun.com, go through your normal support channel.