Once you are an experienced Python programmer it isn't a problem, but it can be a pain dealing with white space sensitivity while you are learning. The biggest problem is that the Python code will *look* right, but not execute.
As an experienced programmer prior learning Python it only caused me mild heartache. I don't know how easy or hard it would be for a total newcomer to programming. If they are some of the people that were in my early CS classes, I'd say they'll never get past it without help.
What problems in Ruby are you referring to that a newcomer will experience? In general, I wouldn't expect someone who is just learning to program to run into any serious difficulties with Ruby or Python (other than significant whitespace).