diff --git a/jquery.flot.js b/jquery.flot.js
index 54807e4..81b4da2 100644
--- a/jquery.flot.js
+++ b/jquery.flot.js
@@ -716,7 +716,7 @@
             canvasHeight = placeholder.height();
             
             if (canvasWidth <= 0 || canvasHeight <= 0)
-                throw "Invalid dimensions for plot, width = " + canvasWidth + ", height = " + canvasHeight;
+                throw new Error("Invalid dimensions for plot, width = " + canvasWidth + ", height = " + canvasHeight);
         }
 
         function resizeCanvas(c) {