and another fan told me this:
Liv and Joaquin are no longer together. Liv is presently dating Ben Affleck's younger brother, Casey Affleck (Joaquin`s friend). This came right from Ben's mouth himself.

So ... what is true? I`d rather believe in Liv`s mother!

Friday, July 17 1998
So here it is what Liv`s mother (Bebe Buell) did say to Liz Smith:

"This is so ridiculous - a joke. And it is so unfair to Liv and her boyfriend of three years, Joaquin Phoenix. It is unfair to Bruce, as well. But I'm here to tell you, he never laid a finger on Liv in any inappropriate way. He respected the fact that she was committed to Joaquin, and I really don't think he is interested in seducing children, anyway. Listen, Liv's father rock icon Steven Tyler was at the premiere in Florida, and if he had even thought there was anything going on, he would have kicked Bruce's ass!"

Buell is outraged that her daughter's natural, affectionate nature might be hampered because of this. "She is a very open, loving person. She hugs and kisses. If anybody saw her hugging Bruce Willis, well, that's just the way she is." What about those stories of Demi Moore reacting violently to Liv being at her house with Bruce. "You mean Liv and Ben Affleck and several other cast members? Bruce flew a lot of people up to his house all the time. I never saw negativity from Demi, nor did Liv ever sense any bad vibes."

you can read it here

Friday, July 17 1998
Here is another quote stated by Joaquin recently (7/98):
"It's a crime to sneak in and take a picture of someone dead. It's a crime and if I ever found out who did that, I would probably end up in prison. Because I would beat the living bleep out of them." Joaquin Phoenix in "Elle magazine" on the coverage of the overdose death of his brother River Phoenix

Thursday, July 16 1998
Just got an email from a Joaquin-fan regarding the Joaquin-Liv - topic:

"well as you probably know livs mother spoke out to liz smith a few days ago and said among many other things that the rumors about Liv and Bruce were untrue and repetatively mentioned her bf of 3 years, Joaquin Phoenix, and how they were cruel rumors and didn't want them to hurt her daughter or her daughters relationship to Joaquin. Well I think that is pretty funny since liv cheated on him so many times with atleast someone from each of her current movies, jake scott, bruce willis (probably) etc etc, she seems like a big time slut and I think he deserves a lot better than her. A friend of mine went to a party that she was at and bruce, ben, gwyneth, harvery weinstein and dan akkroyd among other people not famous but connnected, in a hotel in nyc and said she saw no sign of joaquin, but that liv was up on every male there!! i don't know what is up with them, I think it is very on again off again due to her cheating, I guess at the time of this latest rumor about her it was on again."

Saturday, July 4 1998
Despite sweltering heat during a two-week shoot on a remote Thai island, Vaughn and Phoenix kept each other's spirits high. "When I hang out with Joaquin, I feel like I'm twelve years old in the suburbs," Vaughn says, "and we're going to shoot our BB guns at streetlights."

Well, I surfed around and tried to find some information.
The IMDB says: dated Liv Tyler 1997
At the CelebSites Liv Tyler: companion: Joaquin Phoenix (actor)
One Liv Tyler Page said that they did break up in December.

But I think they really did break up. (I am not one of that jealous fans, I would be happy if Joaquin has such a great and pretty girlfriend like Liv, but it`s probably over now!)

Thursday, July 3 1998
I just surfed around and look what I did find at a casey affleck page: casey`s favorite actor is ... Joaquin Phoenix