float:left and click / hover in IE7. Works everywhere else.

#sideMenu{
  border: 1px solid black;
  border-bottom-width: 0;
  width: 185px;
  float: left;
}

<div class="floatLeft">
  <div id="#sideMenu">
    <ul>
      <li>...</li> etc.
    </ul>
  </div>
</div>

#sideMenu{
	border: 1px solid #858688;
	border-bottom-width: 0;
	width: 185px;
	margin: 0 10px;
	float: left; /*Here is my problem. If I remove this, everything is fine. With this, the menu won't work in IE7, works everywhere else*/
    /*I tried adding z-index here, tried with display: block, inline and inline-block, clear: both, nothing worked*/
}
 
#sideMenu ul{
	margin: 0;
	padding: 0;
	list-style-type: none;
	font-size: 90%;
	text-align: left;
}
 
#sideMenu li a{
	display: block;
	padding: 6px 0;
	padding-left: 9px;
	width: 169px; /*185px minus all left/right paddings and margins*/
	text-decoration: none;
	color: #E1E7EF;
	background-color: #1677EF;
	border-bottom: 1px solid #90bade;
	border-left: 7px solid #1958b7;
}
 
* html #sideMenu li a{ /*IE only */
	width: 187px; /*IE 5*/
	w\idth: 169px; /*185px minus all left/right paddings and margins*/
}
 
#sideMenu li a:hover {
	background-color: #2586d7;
	border-left-color: #1c64d1;
}
#sideMenu li a.current{
	border-left: 7px solid #FF0000;
}
#sideMenu li a.current hover{
	border-left: 7px solid #FF0000;
}
 
#sideMenu h3{
	color: #E1E7EF;
	border-bottom: 1px solid #000000;
	padding: 3px 0;
	padding-left: 5px;
	background-color: #858688;
	font-weight: bold;
	margin: 0;
	text-align: left;
	font-size: 15px;
}

<div id="sideMenu">
<h3>My menu</h3>
<ul>
<li><a href="http://www.google.com">Google</a></li>
<li><a href="http://www.yahoo.com">Yahoo</a></li>
<li><a href="http://www.csscreator.com">CssCreator</a></li>
</ul>
</div>