Kaplan-Meier multiple group comparisons

Question

Lets say I have the following data frame

library(survival)
library(multcomp)
data(cml)
cml$group<-sample(1:5, 507, replace=T)
    plot(survfit(Surv(time=cml$time, cml$status)~factor(cml$group)))
(survdiff(Surv(time=cml$time, cml$status)~factor(cml$group)))

I want to perform multiple comparison test comparing (logrank) for example group0 vs. all other groups or even every group with each other? Is it necessary to correct for multiple comparisons? If yes, is there a nice way of plotting these multiple comparisons (as for example in plot.TukeyHSD() in aov())?

I have posted the same question in http://stackoverflow.com/questions/11176762/kaplan-meier-multiple-group-comparisons but the answer presents multiple comparison test with parametric survival not with non parametric (as in my case)