Using a modalpopupextender on my page and can not get it to open.  When I check the errors through both firebug (FireFox) and the IE Developer Tools console, I get an error stating "TypeError:  $common is undefined" on the line:
this._foregroundElement.style.zIndex = $common.getCurrentStyle(this._backgroundElement, 'zIndex', this._backgroundElement.style.zIndex) + 1; The modal will not open at all and I am at my wits end on what could be causing the issue.  I do have my Scriptmanager switched to a ToolScriptManager control.

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