Unable to login and/or see servers

[erz]

I've spent the past few hours trying everything I can think of to get this to work. Login attempts will either time out or, upon logging in, show a blank server screen. So far I have:

-Uninstalled and reinstalled both the game and EQEmu.
-Changed between both login server addresses.
-Flushed DNS, reset/renewed IP, and ensured port 5998 is not being blocked on my router.
-Called my ISP (Verizon) and had them look into it. They say it's not on their end, if that's worth anything.

It doesn't seem to matter whether I launch directly from the EQGame shortcut or through EQEmu. Just once, randomly, I was able to see servers and got to the character selection screen, but logged out in order to fix a setting (oops) and never got back in.

The strange thing is that I am able to log in from my USB modem (same ISP). Verizon's way of absolving themselves of responsibility was to say because tracert and ping were good, it clearly isn't them. Could something else be getting blocked or denied along the way?