  The anelastic spectra (elastic energy loss and dynamic modulus versus
temperature) of La1-xCaxMnO3 have been measured for 0.33< x < 0.5. A peak in
the imaginary part of the elastic susceptibility is found slightly below the
Curie temperature, whose temperature and frequency dependences are typical of
the dielectric and magnetic susceptibilities of relaxor ferroelectrics, spin
glasses and other inhomogeneous frustrated systems. The fluctuations can be
associated with the magnetic clusters which are observed by several techniques
or with charge-ordered insulating domains in the low temperature inhomogeneous
phase. The temperature dependent distribution function of the fluctuation
energy barriers has been extracted by the analysis of the experimental curves.
