.min_width
{
	min-width: 500px; /* For good browsers */
}
	* html .min_width
	{
		padding: 0 250px;
	}
	/* This is for the markup that only appears in IE6 thanks to conditional comments */
	.min_width .min_width_inner
	{
		width: 100%; /*  gives the element hasLayout */
	}
		.min_width .min_width_container
		{
			margin: 0 -250px;
			position: relative; /* Fixes negative margin bug */
			float: left;
		}

http://www.thecssninja.com/xhtml/ie6-min-width-solutions

Accomplish min-width in IE6 using CSS and conditional comments, no need for expressions.

Pure CSS IE6 Min-width

css, ie6

CSS