Can't send netfirms mail from Verizon iPhone

I've been trying to set up my netfirms hosting email on my new Verizon iPhone and I can't get the Pop settings to working on outgoing mail. Does anyone use their iPhone for the mail on their netfirms hosted site? If so, what settings are you using?

Netfirms says to use:

Hostname: smtp.yoursite.com

Username: youremail@yoursite.com

Password: youremailpassword

I've tried that but it won't work. It defaults to SSL off, port 587. Any help would be greatly appreciated.