datepicker gives jscript error at resolvewith (js script version 1.6.2)

I get an error "Microsoft Jscript runtime error: Object doesnt support this property or method" at the resolvewith point, in the finally block.

Please help

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code from js file below

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resolve with given context and args

resolveWith: function( context, args ) {

if ( !cancelled && !fired && !firing ) {

make sure args are available (#8421)

args = args || [];

firing = 1;

try {

while( callbacks[ 0 ] ) {

callbacks.shift().apply( context, args );

}

}

finally

{ fired = [ context, args ];

firing = 0;

}

}

return this;

},