Dennis and Kimberly Quaid Roll the Dice in Divorce

Dennis Quaid may be overpaying his estranged wife for child and spousal support ... but then again, he might be underpaying, so everyone's quietly gone to court to try and square things up.

Turns out, Dennis and Kimberly Quaid never got a temporary spousal or child support order after she filed for divorce last June. According to legal docs, Dennis has been voluntarily paying for the living expenses of Kimberly and the 9-year-old twins since the split.

We're told they disagreed on how much Dennis should be paying. She thinks he should pay more and he thinks he's actually overpaying.

So, Dennis and Kimberly now say in legal docs -- once a judge sets the amount of spousal and child support -- they will add up what Dennis has paid, and if he's been underpaying he needs to cut a check for the difference. It's a gamble for Kimberly, because if Dennis overpaid she needs to cut a check for the difference.

Divorce ... sometimes it's like Vegas.