R help - Mar 2010 - error message when using mice: missing observations in cov/cor

Hi there,

I am trying to do multiple imputations with the mice package. My dataset
consists of 132 variables and 92 data rows. I specified the predictor matrix
using quickpred, which resulted in about 30 predictors per variable. I am using
norm as imputation method for continuous variables and logreg for categorical
variables.

At various points during the imputation I get the error message: error in
FUN(newX[, i], ...) : missing observations in cov/cor . I tried to exclude some
variables but cannot trace down the problem, as it reappears with other
variables. It seems as if mice imputes NaN for some variables, but I don't
know why. It also doesn't seem to depend on the iteration number. Can anyone
help me?

Thanks, 
Nicole