Monday riddle.

At the San Diego Archaeological Center they have this large urn, that everybody has his own opinion on. Nobody can decipher it’s inscription you see. It reads “Iti sapis spotan dabi gone”.
Then one day, a welder from Santee walks in, asks to see the famous jug, looks at it in the stunned silence that the custodians have grown to expect from visitors on first sighting this piece of crockery.
Then, the man falls over, rolling on the floor with laughter.
What is up with that?