I have heard that the test are not that reliable but who knows...I have also heard that oral can be transmitted to gential,...so if she had a guy with a cold sore go down on her that could have casued this...REMEBER it lays dorminte (sp) she may have already had it and didn't know it...
only tests when there is an outbreeak are reliable because they culture the puss that comes out of the sore but oral herpes like a cold sore isnt the same as a genital herpes.
Maybe she showed up postive because of her mouth sores, because honestly, if you really had hard core sex it can put little blisters down there. However, it can be transmitted from her mouth even though it is two different types of herpes. So be really careful of oral sex i.e if she has an outbreak on her mouth, no blowjobs!!!!