[R] library(survival)-- cluster

[Terry Therneau]

 The query was why survreg() with a cluster() statement fails.  
 The answer: a bug.  A call to resid() preceded setting the class of the
result to 'survreg'.  

  I am currently adding another case to the test suite so that this does
not happen again, and to formally validate that the numeric values are
correct.  I should have it repaired in a day or so; then it will
propogate out from Rforge to CRAN.  I'll send another note when the new
code is present.

	Terry T.