var Acrobat; 
var Flash;
var iChat;
var Java;
var Livemath; 
var QuickTime;
var Powerpoint;
var RealPlayer;
var Shockwave; 
var WindowsMedia;
var Zip;

function isPluginInstalled(pluginname){

	var app=navigator.appName;
	var ie_latest=6.01;
	var ie_required=4.6;
	
	var app_ver = parseFloat(navigator.appVersion);
	var app_ver1 = navigator.appVersion;    
	var app_ver1 = app_ver1.substring(22,25);
	var mimeType = "";

	switch(pluginname) {
		case "Acrobat":
			mimeType = "application/pdf";
			break;
		case "Chime":
			mimeType = "chemical/x-pdb";
			break;
		case "Flash":
			mimeType = "application/x-shockwave-flash";
			break;
		case "iChat":
			mimeType = "application/x-chat";
			break;
		case "Java":
			mimeType = "application/x-java-applet;version=1.3";
			break;
		case "Livemath":
			mimeType = "plugin/x-theorist";
			break;
		case "Powerpoint":
			mimeType = "application/powerpoint";
			break;
		case "QuickTime":
			mimeType = "video/quicktime";
			break;
		case "RealPlayer":
			mimeType = "audio/x-pn-realaudio-plugin";
			break;
		case "Shockwave":
			mimeType = "application/x-director";
			break;
		case "WindowsMedia":
			mimeType = "video/x-ms-asf";
			break;	
		case "Zip":
			mimeType = "application/zip";
			break;
	}
		
	if (app.indexOf('Netscape') != -1) {
		mimetype = navigator.mimeTypes[mimeType]
	  	if (mimetype) {
	    	plugin = mimetype.enabledPlugin
	    	if (plugin) {
				return true;
			} else {
				return false;
	      	}
		} else {
	    	return false;
		}
	} else if (app.indexOf('Microsoft') != -1) {
		if (navigator.platform.indexOf('Win') > -1) {
			if (navigator.mimeTypes[0] != null) {
				pluginname = navigator.mimeTypes[mimeType].enabledPlugin;
			}
			pluginArray = new Array(pluginname);
			for (plugin in pluginArray) {
				if (eval(pluginArray[plugin])) {
	  				return true;
				} else {
					return false;
				}
			}
		} else if ((navigator.platform.indexOf('Mac') > -1)  || (navigator.platform.indexOf('PPC') > -1 )) {
			if ((app_ver > ie_required) || (app_ver1 > ie_required)) {
		 		mimetype = navigator.mimeTypes[mimeType]
	  			if (mimetype) {
	    			plugin = mimetype.enabledPlugin
	    			if (plugin) {
						return true;
					} else {
						return false;
					}  
	  			} else {
					return false;
	    		}
			}  else {
				return false;
	      	}
	  	}
	} else if (app.indexOf('Opera') != -1) {
	 	mimetype = navigator.mimeTypes[mimeType]
	  	if (mimetype) {
	    	plugin = mimetype.enabledPlugin
	    	if (plugin) {
				return true;
			} else {
				return false;
	      	}
		} else {
	    	return false;
		}
	}
}