In an attempt to understand relaxation dynamics associated with the glass freezing transition in a dipole glass of DRADP-x, we examined low-frequency dielectric constant spectra as a function of the temperature. The very weak and broad dielectric spectrum observed at each temperature was analyzed by using the Tikhonov regularization method to derive relaxation time distribution functions at corresponding temperatures. A crossover change in the distribution function was explained in terms of the dynamically correlated domains.