jQuery toggle slide down

For once, I have a script fully working... I have four tabs that pull down when clicked. If a tab is open, and you click another tab, the opened tab closes first, then the selected tab opens.

Here is a working example (Open Tab1, then click Tab2 and note how it closes quickly, i want Tab1 to slide closed, then Tab2 slide open):
http://psylicyde.com/misc/slide-panel

The problem is that the open tab closes abruptly when changing tabs. Is there anyway to smooth it out? Here is my code, with highlights.

$(document).ready(function(){

	$(".btn-slide1").click(function(){
		// first close any other open panels
		$("#panel2").hide();
		$("#panel3").hide();
		$("#panel4").hide();
		
		// then open the selected panel
		$("#panel1").slideToggle("slow");
		$(this).toggleClass("active"); return false;
	});
	
	$(".btn-slide2").click(function(){
		// first close any other open panels
		$("#panel1").hide();
		$("#panel3").hide();
		$("#panel4").hide();
		
		// then open the selected panel
		$("#panel1").hide();
		$("#panel2").slideToggle("slow");
		$(this).toggleClass("active"); return false;
	});	
	
	$(".btn-slide3").click(function(){
		// first close any other open panels
		$("#panel1").hide();
		$("#panel2").hide();
		$("#panel4").hide();
		
		// then open the selected panel
		$("#panel3").slideToggle("slow");
		$(this).toggleClass("active"); return false;
	});	
	
	$(".btn-slide4").click(function(){
		// first close any other open panels
		$("#panel1").hide();
		$("#panel2").hide();
		$("#panel3").hide();
		
		// then open the selected panel
		$("#panel4").slideToggle("slow");
		$(this).toggleClass("active"); return false;
	});	
	 
});

PHP: