From Opera's web site: From w3:
Hmm .. Interesting ..
IE5 also has an issue with positioning, as a positioned element should be positioned to the nearest containing positioned element, not the containing element.
The box is a normal box, laid out according to the normal flow. The 'left' and 'top' properties do not apply.
The box's position is calculated according to the normal flow (this is called the position in normal flow). Then the box is offset relative to its normal position. When a box B is relatively positioned, the position of the following box is calculated as though B were not offset.
From Opera's web site: