Kate's Lawyer: Jon "Clearly Didn't Know What He Was Doing"

Kate Gosselin and her lawyer are fighting back at legal documents filed by Jon Gosselin and his camp claiming her involvement with Dancing With the Stars is damaging the kids.

Kate's lawyer, Mark Momjian, told TMZ, Jon's request for primary custody should be dismissed, arguing Jon's legal documents are riddled with mistakes.

Momjian claims Jon went to the wrong court for child support and wants the case to be thrown out.

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"There is no 'Jon Gosselin' exception to the Pennsylvania law," Momjian states in legal docs.

He told TMZ the papers filed by Jon are "incoherent and filed by someone who clearly didn't know what he was doing."

Jon's lawyer, Anthony F. List, told TMZ recently that "under the right circumstances" he would co-star in another reality show with Kate and his plus 8 brood.