diff --git a/javascript/jquery.fixheadertable.js b/javascript/jquery.fixheadertable.js
index 7415ca7..51e8a93 100644
--- a/javascript/jquery.fixheadertable.js
+++ b/javascript/jquery.fixheadertable.js
@@ -294,7 +294,11 @@
 					
 					var type = options.sortType[number];
 					
-					if (type == 'float') {						
+					if ($.isFunction(type)) {
+						
+						getSortKey = type;
+						
+					} else if (type == 'float') {						
 						
 						getSortKey = function(cell) {
 							
@@ -999,4 +1003,4 @@
 		});
 	};
 
-})(jQuery);
\ No newline at end of file
+})(jQuery);