mvr error in PLS package

All,

I have been using a data set to build pls models for three different soil properties.  Two of the three models run fine; however I receive the following error for the final model.

libs.IC.cal <- mvr(libs.IC.fmla, data = libsdata.cond.cal, ncomp=20,validation = "LOO", method = "oscorespls") 

Error in colMeans(x, n, prod(dn), na.rm) : 
        'x' must be numeric

There are many "0" for this soil property.  Could this cause the error?

Best,
Ross

*******************************************************************
Ross Bricklemyer
Dept. of Crop and Soil Sciences
Washington State University
291D Johnson Hall
PO Box 646420
Pullman, WA 99164-6420
Work: 509.335.3661
Cell/Home: 406.570.8576
Fax: 509.335.8674
Email: rsb at wsu.edu

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