Travel / Traveling with a dog from Hungary to Poland [8]

Hello!

I have to travel with my dog from Hungary to Poland, by bus or train, because the planes are pretty expensive and they would also be very stressful for my dog.

Does anyone know any bus companies (like Eurolines) that accept pets? I'd like to travel from Budapest to Gdansk. It doesn't have to be a direct way, I can change busses if I need to.

Thanks a lot in advance!