Starting point:

domain.com - The default page is a "Choose language" page with 4 language choices.

domain.com/language1/ - default page in specific language 1
domain.com/language2/ - default page in specific language 2
domain.com/language3/ - default page in specific language 3
domain.com/language4/ - default page in specific language 4

Due to the language differences I tend to do language specifik linkbuilding.

I believe the best would be to build links to domain.com/ but expect that anchor texts in 4 different languages would diffuse the benefits of anchor text.

I'm looking for good ideas on how to best work out a link building strategy/approach for the above mentioned problem.

I would suggest defaulting to the main language. If you are targeting 50% danish and 25% english default to danish and then make a menu like overture has http://www.content.overture.com/d/ to select another language.

I'm sure there are scripts out there and IP databases that you could use to feed pages depending on geo location. That would be the best way to do it if you know how to program that.

I would suggest Geo-targeted IP delivery, there are many scripts on the market that are free and are used worldwide I.E Google

Wayne

Geo-targeted IP delivery has been considered, and besides the worries of being banned for cloaking (which is unlikely), it will not solve the problem of anchor text, i.e. 4 different words leading to one domain will diffuse the weight of anchor text for the searchengines - that is unless the SE's "translate" the 4 words and assumes that the site is about "keyword" in 4 languages.

I'm not so worried about the user, but will consider geo-targeted IP delivery to avoid the extra step.