This would imply that Open Source knows no borders.
In practice, borders hamper Open Source work a lot. I have been familiar with the hassle involving MySQLers in Russia and the Ukraine trying to get Schengen (European Union) and US visas for meetings. And I have myself gone through a lot of hassle travelling to Russia and once even (out of my own stupidity and carelessness, though) been denied entry to India when I already was on Indira Gandhi airport in New Delhi.
But now, I've experienced what I had expected the least:
Several Sun Microsystems Inc employees, especially related to the Database Group, have been denied short stay business visas to Australia, over the last few months, as they have been seen to be competing with local Australian businesses unfairly.
I regret to share that this will adversely affect MySQL presence at linux.conf.au in Hobart, Tasmania 19-24.1.2009.
Footnote: The illustration is from the border between Finland and Russia. When I grew up, it used to be a very closed one.
Update / clarification
I am overwhelmed by the attention this post has got! It's been quite a ride, and a lesson in blogging. In retrospect, I should perhaps have anticipated the level of interest, and spent time fine-tuning my wording. I didn't, so there's a need for clarifications and an update for anyone who doesn't want to read all the over 30 comments.
First: Personally, I am not the one to have been declined a visa to Australia. The person whose visa was affected is a close colleague, but not myself. I've been several times to Australia, both prior to and after joining MySQL AB, and I have never had any issues.
Second: Given my frustration at the rejection of the visa of my colleague, I chose to use the word "several" to describe two instances.
Third: The first instance, in August 2008, is referred in detail in Comment #29. Not thinking I was providing a scoop for The Register, Heise Online and the Australian Broadcasting Corporation, I didn't even look up that chat log until replying to the commenters on the blog. And in that first instance, the person in question ("kv") had already got a visa. He was not denied a visa. However, the interaction over instant messaging with "local_mysql_activist" implied that the visa could be overturned by the immigration authorities at the border, so "kv" did not dare go try his luck. I apologise for the inaccurate wording on my part, as it's technically not true that "several" MySQLers would have got their visas rejected (although I can assure you that's how "kv" personally feels).
Fourth: The connection between the first instance and the second instance, where my close colleague was rejected a visa, is not evidenced by any official information from the Australian government. The rejection letter merely says Ã¢â‚¬ÂSHORT TERM BUSINESS ETA APPLICATION WAS NOT APPROVED NO AUTHORITY TO TRAVEL TO AUSTRALIA HELD BY PASSENGERÃ¢â‚¬Â. However, the person who now got rejected has been frequently in Australia and, to the best of my knowledge, lacks any record which would imply a visa rejection (such as, but not limited to, unpaid traffic fines).
Fifth: Some readers have asked me whether I see an Australian anti-open-source conspiracy. Definitely not! The trip was related to an open source conference, and the applicant went by the book, asking for a short-term business visa where many frequently travel on tourist visas for equivalent purposes. Thus, the denial could be the result of an overzealous bureaucrat in the aftermath of #29. But that assessment is firmly in the realm of speculation and has no claim on objectivity.
Sixth: Thanks for all the offers of help! However, by now, linux.conf.au is so close that we canÃ¢â‚¬â„¢t appeal this. Flights have had to be cancelled, and are now either full or horrendously expensive. So the harm has been done (for whatever the reason may be) and Sun / MySQL won't be represented at linux.conf.au at the level originally intended. Some of us will still come, though.
Finally, I'm deeply grateful for all the sympathy and support we got. Thank you!