This, for the most part, works on the Solaris 10u4 system I tested on.
I was running JDS R3 and when I click on the "Learn More" button or
some other link in Update Tool it brings up Mozilla. I say "for the
most part" because I have my preferred browser set to Firefox, but at
least the link is displayed in a browser.
On another S10u4 system with the CDE desktop it does not work at all
which is not surprising.
Arvind, where you using JDS (the gnome desktop)?
In Preferences->Desktop Preferences->Preferred Applications what
is your Web Browser setting?
It would also be interesting to see if this is imporved in a later
release of Solaris 10.