Vibrational wave packets in the B (1)Pi (u) and D (1)Sigma (+)(u) excited states of Cs-2 have been studied on the similar to 100 fs time scale by pump-probe laser spectroscopy. The temporal behavior of the wave packets was monitored by photoionizing the electronically excited molecule with a time-delayed probe pulse and recording the time and energy-integrated photoelectron signal as a function of time delay between the pump and probe pulses. For the B (1)Sigma (+)(u) experiments, wave packets were produced by exciting the B (1)Sigma (+)(u)<--X (1)Sigma (+)(g) transition in the similar to 740-790 nm region and subsequently detected by photoionizing the molecule at wavelengths between 565 nm and 600 nm. By simulating the experimentally observed transients with the density matrix formalism (and explicitly accounting for laser chirp and \Deltav\>1 coherences), improved values for the equilibrium internuclear separation for the Cs-2(B (1)Pi (u)) state and T-e for the Cs-2(+)(X) state were determined to be R-e(B (1)Pi (u))=4.93 +/-0.03 Angstrom and T-e[Cs-2(+)(X)]=29 930 +/- 100 cm(-1), respectively. Similar experiments were conducted for the D (1)Sigma (+)(u) state. Wave packets composed of vibrational levels (v(')approximate to 40-50) perturbed by the bound 2 (3)Pi (ou) state were produced on the D (1)Sigma (+)(u) potential surface by driving the D (1)Sigma (+)(u)<--X (1)Sigma (+)(g) transition in the 575-610 nm spectral interval.