Molecular structures, harmonic frequencies, and binding energies of M(2)H(6) hydrides (M = B, Al, Ga) have been computed using recently introduced density functionals incorporating gradient corrections and some Hartree-Fock exchange. Structural and energetic quantities computed by the new functionals are in good agreement with the available experimental data and represent a significant improvement with respect to the results obtained by standard density functionals and conventional post-Hartree-Fock methods.