What steps will reproduce the problem?
1. just try to retrieve element by css locator and use :contains selector.

Java example:
WebDriver driver = new FirefoxDriver();
driver.get("http://localhost:8080/");
WebElement webElement = driver.findElement(By.cssSelector("a:contains('Text')"));


With FirefoxDriver it throws:
org.openqa.selenium.WebDriverException: An invalid or illegal string was specified

with HtmlUnitDriver it throws:
com.steadystate.css.sac.TestCSSParseException: Error in pseudo class or element. Invalid
token "Text". Was expecting one of: <S>, ")", <IDENT>.


What is the expected output? What do you see instead?
WebElement is found and no Exception threw.


What version of the product are you using? On what operating system?
Selenium 2.0a7


System info: Fedora13, 64b, kernel: '2.6.34.7-61.fc13.x86_64', java.version: '1.6.0_21'.