HTML Table row heights will typically change proportionally to the table height, if the table height is larger than the height of your rows. Since the table is forcing the height of your rows, you can remove the table height to resolve the issue. If this is not acceptable, you can also give the rows explicit height, and add a third row that will auto size to the remaining table height.
Another option in CSS2 is the Max-Height Property, although it may lead to strange behavior in a table.http://www.w3schools.com/cssref/pr_dim_max-height.asp
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