This script is designed to change the apparent OS version of Solaris, as reported by uname -a, to bypass software installation sanity checking. Ie. you can fake the solaris OS version. This is useful is you have COTS software that requires specific OS versions, and you want to try a different, newer OS version. The mechanism used is to modify the running kernel via ADB from a script.
You probably should NOT do this in a production environment.
A similar goal with a less intrusive implementation is available here: Ben Stern's libuname.
If you are using Solaris 10 (or later?) you can do this with dtrace: Changing uname output with dtrace
And here's an implementation that uses a loadable kernel module: sloggi