Danijel,
We have a problem with allocated address range to CARNet (Croatian Academic and Research Network) which RIPE have assigned to us a few months ago. The range is 82.132.0.0 /17.
Some of the world wide companies keep old records about IP addresses in their databases so that makes problems to our users.
Sadly there is little or nothing this group can do for you. We would strongly advise networks to be very careful when maintaining their own blacklists or with which services they use as stale information can lead to incidents such as you are expeiencing. And this is likely to happen more and more as exhaustion approaches as more and more space is used.
Please, can anyone advice us what we can do concerning this problem.
The best advice I can give is to contact the relevant large companies and inform them that the space has now been allocated to CARNet (with approriate Whois links etc) and ask them to remove their blocks. As with all such things, their networks, their rules, but hopefully the knowleged that they are losing out on quite a few potential customers will encourage them to quickly update their rulesets. If the companies use services As Thor mentioned, you may also be able to find out which geolocation services are being used and go to the source of the problem, but these may vary on a company by company basis. Regards, Brian.