Dreamhost is vicious with the memory limits. I believe they also kill off processes that are taking too much CPU or resources at random. This is what you get for cheapo unreliable shared hosting.
Here's the output of your image:
http://www.ceccarelli.ind.br/photo/Fotos_2007/2007.10.12%20-%20Casamento/Final/image/thumb/1.jpg
Note the error message - memory limit exceeded. It doesn't matter if other images work, because it's *not* the JPEG file size that matters, but the Bitmapped internally stored image, which can vary based on many factors. But, you can be assured, if images are not caching it's very likely hitting the memory limit.
Just make your images smaller, or get a new host who's less restrictive. Don't bother asking Dreamhost for more memory, they'll likely close your account for abusing resources.