Ok, I can't find the post explaining this so I'll be a nice guy and explain why that won't work
Every CD of a certain era that EQ was distributed on isn't the same client. There are way too many client/server mismatches. That's why the only client that came specifically with the Titanium distribution will work.
There seems to be some mixed feelings within the community about this route. I seen a couple or so that has the opinion that the dev's should keep updating live. Me personally, I like the titanium route much better because the updates are oh so much faster AND if I accidentally patch (which I done before and broke it hehe), I'm SOL :P So, it's well worth the 19.99 to buy the Titanium CD's