troubleshooting ports being blocked across country borders

[etherbadger]

I have a client in the United States with a large customer/vendor base in Brazil. Ive sent them repeated instructions on how to set up a VPN to the US server. I have configured a laptop vpn myself which worked fine stateside but didn't connect after being sent to Brazil. I had logmein on the laptop but that is also being blocked somewhere, it happens when my clients at hotels or the vendors' networks so I suspect its an ISP issue.

Does anybody have tips on how to go about troubleshooting connection problems like this across national borders? I should also mention that I don't speak Portuguese and most of the Brazilian staff don't speak English.