Trademark a domain name

[virtualreality]

I own a domain name, for example example.com
Someone else owns example.asia and they want to trademark it. How will this affect my domain name?
Also, where is a good place to trademark a domain name and how exactly does it work?

[edited by: buckworks at 7:52 pm (utc) on May 10, 2010]
[edit reason] Plese use example.com - it will never be owned [/edit]

[piatkow]

where is a good place to trademark a domain name

I would imagine that the best place would be the appropriate agency for the jurisidiction in which you do business. As that could be in any one of 195 sovereign states its a bit difficult to be precise.