Background-attachment: fixed image moves unexpectedly, is not repainted correctly at body's margin-right in 4

Steps to reproduce: scroll up and down the webpage.

Expected results: the thin blue horizontal lines should not get broken when scrolling up and down.

Actual results in Konqueror 4.3: the thin blue horizontal lines get broken when scrolling up and down.

Original webpage where the problem was first noticed: Alan Gresley's Escaping Background image bug

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