I have just recently installed webmail extension for my thunderbird and I want to download my Yahoo mail into it.  For webmail to work, it needs to open ports 110 for pop3 and 25 for smtp connections.  I know at the root level, these two ports are open, but at the user level anything up to 1024 are blocked.  For now, I just used two ports above 1024 to make webmail work.

Is there a danger in opening ports 110 and 25?  I am guessing that I only need to open them for the localhost 127.0.0.1.  If it is okay to open it, how do go about doing it?

Your help is kindly appreciated.