Looks like an actual bug. This should fix it:
Code:
<a href="javascript:up();" onclick="return false;" onmouseover="myspeed=-thespeed" onmouseout="myspeed=0"><img
src="arrows_up.gif" border="0"></a><br>
<a href="javascript:down();" onclick="return false;" onmouseover="myspeed=thespeed" onmouseout="myspeed=0"><img
src="arrows_dn.gif" border="0"></a>
Notes: The dark red additions are just to affect the status bar or other link report(s) of the browser to give the user a better idea of what the controls do. Just about anything can go there. The bright red additions are the real fix, preventing the browser from executing the href attribute onclick which would otherwise produce the error you are seeing.
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