Wanted to post here on my recent (July 2008) experiences with trying to get my marriage recognised in Finland.
The important details are
*We are 2 non Finns living permanently in Finland
*We are EU citizens
We went back to the UK and got married, came home to Helsinki and wanted to get my wife's name and our civil status' changed in the population register. The Maistraati in Helsinki said they couldn't accept a UK wedding certificate without an Apostille. We wondered what one of those was! We used google. For those of you who are Brits we checked with the embassy in Helsinki who told us we had to send the original certificate back to the FCO in London, pay the fee and it would come back legalised. This we did and sure enough it worked.
So we went back to the Maistraati who took one look at it, said thank you very much, got us to fill out half a form and we were done. No problems. Nada.
So if you get married abroad and need to let the Finnish authorities know it may save you some time to look into apostilles.
Hope this helps
Cheers
Donpeblo