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This issue intermittently affects various versions of the iPhone however ive not heard any complaints from the new iphone 6, but it does mostly affect IPhone 4S and iphone 5 to some degree as well I have also seen reports of it being an issue with ios6

This thread discusses the issue

https://discussions.apple.com/message/9503536#9503536

this suggestion should get things workign again:
>>First, delete the account in question on the IPhone. Next recreate it. At some point it says "The certificate may not be valid." And when it asks whether to continue without SSL or encrypted passwords, hit "continue" and wait for it to check its settings and confirm everything is OK. This process causes it to connect without a certificate. Once it has done that, you can check mail normally. You can even go back to the settings and tell it to use SSL and now it will succeed.

Another comment I thought was interesting in that it will only work properly when you use the server hostname so enter the mail server as mail.ethicalhost.ca (if you have not already) and see if that makes a difference (another forum I found mentioned this >>The only thing that seems to help is to change the incoming mail server; for example: change from mail.ethicalhost.ca to ethicalhost.ca. So you could change it to just ethicalhost.ca instead of mail.ethicalhost.ca as an option.

Another option is setting the inbox imap folder on the phone:
1.    If you set up the IMAP mail account on your iPhone, you may not  find the IMAP folders in your Inbox folder. If this is the case, you'll need to specify the IMAP path prefix.
2.    You can enter in the IMAP path prefix by going to Settings > Mail > Account > Advanced > IMAP Path Prefix.
3.    Enter the word "INBOX" (use all caps) and save the setting. Now, your folders should appear as subfolders in the Inbox.