Britney Spears has been making late-night phone calls to K-Fed in hope of a reconciliation, so say several of Kevin's close peeps. They tell TMZ that Britney's relationship with Isaac Cohen is a ruse to make Kevin jealous.

But other sources -- frankly, the ones that ring true for TMZ -- say Britney is so over him. They tell us that Brit and the Fed have very little contact, and when they do communicate, it's about their two kids.

By the way, according to these sources, the reports that Britney will ante up $25 mil to K-Fed to end their marriage are ridiculous. One source says the $25 million figure is grossly inflated, "by 25 times." In other words, the bad news is that K-Fed will be a millionaire. The good news -- just barely.