IE/Firefox and CSS nested lists sublist shows horizontal to parent in FF but not in IE

Hi,

I wanted to have a nested CSS-styled list where the subelements would show horizontal (on the same level) as parents.
While FF does it as it should, the IE...figures...does not.

As snippets:
HTML LIST:

First heading

• List item 1

(...)

CSS STYLING:
.headings {
font-size: 12px;
font-family: Verdana, Geneva, sans-serif;
font-weight: normal;
text-transform: uppercase;
text-align: left;
font-weight:bold;
color: #B82129;
padding-bottom: 5px;
padding-top: 5px;
}

.projects {
font-size: 11px;
font-family: Verdana, Geneva, sans-serif;
list-style-type: none;
}

.projects ul {
margin: 0;
list-style-type: none;
}

.projects li {
margin: 0;
padding-top: 1px;
padding-bottom: 1px;
display: inline-table;
}

.projectthumbs {
font-size: 14px;
}

.projectthumbs ul {
height: 10px;
padding: 0 0 1px 15px
}

.projectthumbs li {
float: left;
list-style-type: none;
height: 12px;
width: 12px;
margin: 0 3px 0 0;
display: inline-table;
}

.projectthumbs li a{
padding: 0;
color: #FFFFFF;
background-color: #999999;
width: 8px;
height: 12px;
padding: 0 2px;
display: block;
}

.projectthumbs li a:active {
background-color: #B82129;
}
.projectthumbs li a:hover {
background-color: #B82129;
}

/*.projectthumbs li a:visited {*/
/* background-color: #433e39;*/
/*}*/

Sorry for messy CSS, I have some redundancies which I have to still work on...

Here is the FF and IE7 rendering:
FF:
IE7:

The code could be found at: http://www.shepdev.pcriot.com/list.html