repulsive classical gravity

Could one make classical gravity repulsive on large scales by this particular change L=(Φ)2/2+4πGρΦm2Φ2/2, giving rise to the modified Poisson equation, (Δ+m2)Φ=4πGρ, and how would that modification differ from introducing a cosmological constant? What would be the interpretation of m in the Lagrange-density?