Very good. I have a DSL with private IPs static and public IP assigned dynamically. I have used similar method for ages.
I'm replying, because your link does not give correct information. For me, it reports a completely wrong host. (probably a proxy or something similar)
I use:
http://grc.com/default.htm and click shieldsup/test my shields. This gives me my correct public IP everytime.
I suggest people first TEST what gives correct information before blindly accepting information and inputting it to LimeWire.
B Rgds,
Maccara