diff --git a/src/jquery.maskedinput.js b/src/jquery.maskedinput.js
index 545e693..79175be 100644
--- a/src/jquery.maskedinput.js
+++ b/src/jquery.maskedinput.js
@@ -159,7 +159,12 @@
 
 						var p = seekNext(pos.begin - 1);
 						if (p < len) {
-							var c = String.fromCharCode(k);
+							if (settings.upcase) {
+							 	var c = String.fromCharCode(k).toUpperCase();
+							} else {
+							 	var c = String.fromCharCode(k);
+							}
+							
 							if (tests[p].test(c)) {
 								shiftR(p);
 								buffer[p] = c;