During the wedding, the priest clearly says that he is marrying Pam and Tommy by the power vested on him by the State of Quintana Roo, however in Mexico priests and other religious figures are prohibited to celebrate civil weddings -they can only perform religious ceremonies-.
During Pam and Tommy's engagement and wedding montage, which takes place in 1995, the song "Steal My Sunshine" by Len is playing. But "Steal My Sunshine" wasn't released until 1999.