[jQuery] SlideToggleUp, this.options.curAnim is undefined

[jQuery] SlideToggleUp, this.options.curAnim is undefined

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.hmmessage P
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body.hmmessage
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font-family:Verdana
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Hi,
I am running into the error "<span class="objectBox objectBox-errorMessage hasTwisty hasBreakSwitch">this.options.curAnim is undefined" for the method SlideToggleUp.
this.options.curAnim[ this.prop ] = true; jquery-1.3b1.js (line 3827).
The problem occurs when I am trying to close a window using this code:
            $('#windowMin').bind(
                'click',
                function()
                {
                    $('#windowContent').SlideToggleUp(300);    /// <------ PROBLEM
                    $('#windowBottom, #windowBottomContent').animate({height: 10}, 300);
                    $('#window').animate({height:40},300).get(0).isMinimized = true;
                    $(this).hide();
                    $('#windowResize').hide();
                    $('#windowMax').show();
                }
            );
I can comment out the row that is causing this error but it does not look very nice.
Any ideas how to solve this?
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