Oh Momma!

Ivan Reitman’s “The Twins Project,” which Universal is set to begin in late March for a big Christmas release, is not to be confused with Fox’s “Twins,” which David Cronenberg is shooting in Toronto.

Cronenberg’s “Twins” is a thriller about rival doctor brothers (both played by Jeremy Irons) in love with the same woman (Genevieve Bujold).

The Reitman film (by the writing teams of Osmond & Davis and Weingard & Harris) is a comedy, and the brothers in question aren’t physically identical. The production casts Arnold Schwarzenneger and Danny DeVito as less than amicable siblings. Years earlier, the two were part of a backfired experimental genetic operation--one brother got the looks, strength and intelligence, the other. . . .

Fed up with second place, DeVito decides to rid himself of fraternal comparison.

A wiseacre in the industry dubbed the film: “Throw Arnold From the Train.”