Just to confirm, I have copied the code as posted on the original thread and it works fine for me.
As I said my sub is almost identical and users have not had an issue with it.
could it be a corrupt installation? or something in the way your email setup is configured.
If you could do a small program that shows the fault and post up the apk and the source, I will install the apk on my device and see if it works, and compile it on my setup and see if that works.
Other than that I am out of ideas.