R help - Apr 2011 - ctree and survival problem

Dear all,

I was intrigued by the ctree command and wanted to check it out. I first ran the
demo with example(ctree) and did get the survival graphs in the end. Upon doing
this with my own data and yielding a "Invalid operation on a survival
time" I tried to rerun example(ctree) and now I also get "Invalid
operation on a survival time" after the example runs plot(GBSG2ct)... any
ideas what is going on here. I?m running R 2.11.1

//M

Forgot to mention that the ctree command is from the party library.
//M