Correct. CC99 is not much more than the European release of HH98 (with a delay of more than one year, unlike all other Jazz games, which were published first in Europe, then in the US).

Nevertheless, it has some improvements compared to HH98: for example, a fancy new menu screen, snow in the menu, Lori etc.
Not to forget that it made (or should make) some Jazzer legends proud, because their names are mentioned in the credits (that's because all of the levels that got into the P2 level contest are included, like martin's "Fright Night CTF").

However, i guess it's a collectors item; nothing that'll give you actual Jazz playing fun (well, apart from those very good five levels, of course).