jQuery tabs w/simpleviewer displays differently in ie & ff

jQuery tabs w/simpleviewer displays differently in ie & ff

test page is at http://www.mangosteenarts.com/test/test3/tabs1.html
There are several major differences in how this displays in IE and
Firefox
IE Firefox
tabs square edges tabs rounded edges
horizontal scroll bar no scroll bar
viewer confined within jQ tab viewer extends beyond jQ
tab
substantial top margin slight top margin
slight bottom margin square corners very large bottom margin w/
rounded corners
Why is this? Is there any way to normalize the cross-browser display
properties?
Thanks.
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