cluster, mona error

Hi

I have a problem using the package cluster on my binary data. I want to 
try mona at first. But i get the an error.

hc<-read.table("all.txt", header=TRUE, sep="\t", row.names=1)
srt(hc)
`data.frame':   51 obs. of  59 variables:
 $ G1p : int  2 1 1 1 1 1 1 1 1 1 ...
 $ G1q : int  1 1 1 1 1 1 1 1 1 1 ...
 $ G2p : int  1 1 1 1 1 1 1 1 1 1 ...
 $ G2q : int  1 1 1 1 1 1 1 1 1 1 ...
 $ G3p : int  1 1 1 1 1 1 1 1 1 1 ...

m<-mona(hc)
Error in mona(hc) : All variables must be binary (factor with 2 levels).

I find this strange when the cluster dataset "animals" have the same 
structure as my data.

srt(animals)
`data.frame':   20 obs. of  6 variables:
 $ war: int  1 1 2 1 2 2 2 2 2 1 ...
 $ fly: int  1 2 1 1 1 1 2 2 1 2 ...
 $ ver: int  1 1 2 1 2 2 2 2 2 1 ...
 $ end: int  1 1 1 1 2 1 1 2 2 1 ...
 $ gro: int  2 2 1 1 2 2 2 1 2 1 ...
 $ hai: int  1 2 2 2 2 2 1 1 1 1 ...

m<-mona(animals) #works fine

what is this error trying to tell me?
mvh
morten