In this work we discuss a short range version of the p-spin model. The mode
l is provided with a parameter that allows us to control the crossover with
the mean field behavior. We detect a discrepancy between the perturbative
approach and numerical simulations. We attribute it to nonperturbative effe
cts due to the finite probability that each particular realization of the d
isorder allows for the formation of regions where the system is less frustr
ated and locally freezes at a higher temperature. [S0163-1829(99)02501-1].