I suspect this is due to a bug in cssQuery, which Selenium currently uses to locate elements by CSS. Details of the issue and a patch can be found in the comments of the following issue: http://jira.openqa.org/browse/SEL-698
Hope that helps - I believe Selenium 2 will be using a different library for CSS locators - possibly JQuery's Sizzle (http://sizzlejs.com/), which should solve this problem.
Dave.
Answer from Dave Hunt on Stack OverflowI suspect this is due to a bug in cssQuery, which Selenium currently uses to locate elements by CSS. Details of the issue and a patch can be found in the comments of the following issue: http://jira.openqa.org/browse/SEL-698
Hope that helps - I believe Selenium 2 will be using a different library for CSS locators - possibly JQuery's Sizzle (http://sizzlejs.com/), which should solve this problem.
Dave.
To avoid painful CSS issues like this, I've installed jQuery as a user extension. It gives the ability to define a locator String similar to CSS ("jquery=td.dt-col-status div.dt-liner:contains('Complete')") that is much more powerful. I can expand on how I did it for the Java RC if you'd like.