thailand multiple enter/visa ???

hello everybody,
I'll travel to south east asia with my wife next january and stay there for about 2 months.
We'll fly from rome to bangkok and fly back from phuket to italy; as an italian/finnish couple,we dont need a visa if we stay in the country for more than 30 days. So our plane is to move around from bangkok to laos first and than to cambodia and then back to thailand(phuket);
We would enter to thailand 2 or 3 times but always for periods shorter than 30 days.
If we have a 60 days ticket,do we have to show/prove somehow that we will go out from the country during these 60 days or it is just enough to get out and come back and air company or custums wont make problems?
thanks everybody for any suggestion
Luca

The rules for the 30-day visa exemption say you need to have "proof of onward travel" within the 30 days. That means an airline ticket out of the country (bus and train don't count). Thai Immigration never checks, but airlines do, meaning you could be denied boarding if you don't have a ticket out of Thailand within 30 days OR a tourist visa. The solution: get a 60-day tourist visa from a Thai embassy or consulate for your first entry into Thailand. All subsequent entries could be done on a 30-day exemption.

thanks for reply billp...
i think the other solution otherwise is to get some cheap flight ticket in advance to cambodia which will prove that we leave thailand within 30 days...then when we fly back from cambodia we will have other 30 days...

Or get a double entry tourist visa.