upon changing month/year drop down date field turns to non edit mode

What steps will reproduce the problem?

1 : implement jqgrid with one field ad date and allow only future date and 
alledit as true.

code snippet:

 {
                        name: 'ExpireDate', align: "center", index: 'ExpireDate', width: 105, sorttype: "date", formatter: 'date', edittype: 'text', editable: true,
                        editoptions: {
                            dataInit: function (el) {
                                $(el).datepicker({ minDate: 0, changeYear: true });
                            },
                            dataEvents: [
                            {
                                type: 'keydown',
                                fn: function (e) {
                                    e.preventDefault();
                                }
                            }]

                        }

click on respective date cell, datepicker will open , now change month/yr, now 
observe that date cell will be turned to NON EDIT Mode.

Error:

Unhandled exception at line 166, column 225 in 
http://localhost:34827/Scripts/JQGrid/js/jquery.jqGrid.min.js

0x80070057 - JavaScript runtime error: Invalid argument.

What is the expected output? What do you see instead?
Upon changing month/yr in dropdown, respective date field should say in EDIT 
MOde only 

Please provide a URL to a page displaying the problem.

What version of the datepicker are you using? On what operating system? And 
Which Browser?
Win7 64 bit / IE9 and FF

Please provide any additional information below.

Original issue reported on code.google.com by chethan8...@gmail.com on 1 Apr 2014 at 5:16

parmarmayur9090 / jquery-datepicker

upon changing month/year drop down date field turns to non edit mode #379