Why does this random, unexpected horizontal line appear in IE7?

I am using YUI's datatable (http://developer.yahoo.com/yui/datatable/) to make a table. But notice something very wrong...sometimes, there is a line that appears on top of a res开发者_如何学运维ult, only in IE7.

This may or may not be related to the YUI plugin. Does anyone know how to fix this? Thanks.!

Edit: For some reason, it only appears at that pixel. (not necessarily at that result...but at that height from the top)

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Check THe html code is there any difference for that row ? any at all.