Derick Rethans has a few humorous comments in his latest blog post about people that submit PHP bug reports and feel compelled not to give good information on it because of "legal reasons".

Some times people don't want to submit their code when filing a bug report for PHP because of "Legal Reasons". They simply assume we can fix it even with their very vague reasons. Usually we persist in asking for more information because we're nice and want to help those people who think they found a bug anyway. Sometimes this gives hiliarius responses. Come on, your uber-cool "new technology" with PHP - we're that ones that gave you the tool to write your "new technology" in the first place. Even better is when they claim that "they're not allowed to tell you what it is".

Yeah, these are specific examples, and most of the reports lack the info they need because the reporter just doesn't know what needs to be included, but that's still no excuse to voluntarily withhold information on how the bug came up...that's just asking for people to ignore your bug report.