[STATSGRASS] sites import problem

[javier garcia - CEBAS]

Hi;
I've imported a sites file into R, but get the following warning messages:
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> Cotas <- sites.get(G, slist="cotas_5000", debug=FALSE)
> ls()
[1] "Cotas"  "G"      "system"
> summary(Cotas)
      east            north              var1
 Min.   :632206   Min.   :4163710   Min.   :   0.00
 1st Qu.:657634   1st Qu.:4174570   1st Qu.:  65.13
 Median :666414   Median :4179580   Median : 140.00
 Mean   :    NA   Mean   :     NA   Mean   : 161.71
 3rd Qu.:676889   3rd Qu.:4184840   3rd Qu.: 240.00
 Max.   :688899   Max.   :4198600   Max.   :1116.18
Warning messages:
1: Integer overflow in sum(.); use sum(as.numeric(.))
2: Integer overflow in sum(.); use sum(as.numeric(.))
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I can't understand the consecuences of this warning nor how to avoid it
Any help?

Javier