Indeed, this definitely needs to go in the docs -- thanks for letting me know. I've updated the relevant doc page (https://www.labkey.org/wiki/home/Documentation/page.view?name=checkin) as follows:

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**Note:** As of October 2009, you must be running **Firefox 3.0,** ~~not 3.5,~~ to successfully run the DRTs. If you are running Firefox 3.5, the DRT will fail when it cannot find certain buttons. A typical error message you might see is 'No button found with text "Delete"'. In theory, you are can have both versions of Firefox installed, as long as you specify the path to Firefox 3.0 when you run the DRT. You can use something along the lines of:

ant drt -Dselenium.browser=*firefox3 c:Program FilesMozilla Firefox3firefox.exe
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Thanks,

Elizabeth