Android iCloud mail setup problems

I have been unable to succesfully setup iCloud on an HTC One X+

I have followed Apple recommended settings exactly.http://support.apple.com/kb/HT4864

I use iCloud on outlook with the same settings and do not have any problems

I have read quite a few threads/posts on this topic and tried any number of variations on the settings but to no avail.

When I add the account the phone verifies the settings

I receive emails without any problems

When I set the account up for the first time I can successfully send an email but subsequently it stops working

The curious thing is that if I send an email from another account to iCloud and then reply, the reply is always sent without any problems

I do not get any error messages so the phone thinks it has sent the email successfully but it is getting lost somewhere in cyber space or on apples servers

Any thoughts?