All the sources I checked confirmed that it is quad band. I would be compatible with the European GSM carriers . If you want to use it with a foreign SIM card, you need to confirm it is unlocked (will accept a foreign SIM).
I recently bought a Samsung SGH-A187 to use on an upcoming trip to Europe. This phone is advertised on many web sites (including newegg, where I bought it) as being a quad-band (850/900/1800/1900 MHz) GSM phone, but the user manual refers to it as a "Portable Dual Band Mobile Phone". I called Samsung, and they eventually told me it was dual band, but the guy I talked to didn't seem sure -- I think he may have been looking at the same at&t manual that came with my phone. I contacted newegg, no help at all.
So now I have this phone and have no idea if it will even work when I head over to Italy. I was wondering if this might help -- I have an old SIM card somewhere (if I can find it) from a European carrier I used on a previous trip. If I can find that and put it in this new phone and the phone is NOT quad-band, will it give me some kind of error when I boot it up to indicate that the SIM card is not compatible?