Near-infrared JHKL photometry of more than 200 stars in the open clusters Tr 14, Tr 15, Tr 16, Cr 228, and Cr 232 in the Carina Nebula is presented. By comparing these results with the available visual photometry and spectroscopy, it is found that the intracluster reddening is characterized, except in Tr 15, by a 'normal' extinction law for lambda greater than 0.5 micron, but is highly anomalous and variable in the U and B bands. Provisional two-color visual polarimetry suggests that the wavelength of maximum polarization is similar to that in the general interstellar medium. This behavior may be explained by the presence of intracluster interstellar grains 'processed' by the passage of shock waves, presumably associated with the violent history of Eta Carinae.