OK, he was using Lynx on Solaris, which is certainly an unusual combination. However, just because he was using Lynx doesn't mean that he was arrested for that fact: the unusual user agent string just highlighted the fact that he was (to use the article's words) "doing strange things" (ie. possibly hacking into the site).
I'm sure the justice system will take its course and we'll get a fuller story later which will probably be more accurate.
If nothing else, this story points out the need to accurately interpret your access_log files.
Seems to me they could have done some searching of the UA string and been, shall we say, possibly more enlightened...rather than what appears to have been a knee-jerk reaction. That is, the assumption that irregularities equate to a hack.
The site-operator decided that this "unusual" event in the system log indicated a hack-attempt, and the police broke down the donor's door and arrested him.
This doesn't mean that he was actually attempting to hack the tsunami-relief web site. It means that an operator thought that using Lynx was indicative of criminal intent. It's a case of ignorance leading to paranoia. Whatever you do, don't be different, or the thought police will get you.
BTW, IE users should not be arrested if they're using it in preference to NN4 :)