Finally, i found a meter! And it turned out to be that the frame was actually 52 cm (both top tube and seat tube is 52 cm). What a shame. Sorry to my LBS for the swearing. The bike is a Scott Speedster Ltd. I think this is the same frame i have:

http://i185.photobucket.com/albums/x...e/DSCF8851.jpg

Now, if i get a shorter stem i'll fix the issue, right? Actually i'm not sure this is the right move because when i sit on the proper place of the saddle i feel like my butt is too far way back than it should be. It feels like i have to strecht out my feet to reach the pedals. I should try that weight hanging method to be sure i guess.