Oracle 10g seems to depend on SUNWsprox - Sun workshop Bundled 64-bit make library. The x termination stood for 64 bit libs in the pre Solaris 10 days, but this no longer applies. The package you actually want is SUNWsprot.
# pkginfo | grep SUNWsprot
system SUNWsprot Solaris Bundled tools
Oracle actually needs libmakestate.so.1. As we can see, that is provided by the SUNWsprot package (part of Solaris 10).
# grep libmakestate.so.1 /var/sadm/install/contents
/usr/lib/amd64/libmakestate.so.1 f none 0755 root bin 12432 31159 1172201465 SUNWsprot
/usr/lib/libmakestate.so.1 f none 0755 root bin 9080 44832 1172201465 SUNWsprot
During the install, it will print out:
SUNWsprox package not installed
If you have the SUNWsprot package installed, you can safely ignore this message.