[Koha] IE error trying to save System Preferences

When I try to modify any of the System Preferences with IE I get the following error: User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0; Trident/4.0; GTB7.0; SLCC1; .NET CLR 2.0.50727; MDDC; .NET CLR 3.5.30729; .NET CLR 3.0.30729; .NET4.0C) Timestamp: Sun, 22 May 2011 21:21:23 UTC Message: 'this.localName' is null or not an object Line: 40 Char: 17 Code: 0 URI: http:// <http://"%3cserver_name_removed%3e":8080/intranet-tmpl/prog/en/js/ajax.js> "<server_name_removed>":8080/intranet-tmpl/prog/en/js/ajax.js Does anyone have any ideas what would cause this error? Firefox form the exact same client machine is able to modify and save the System Preferences successfully. Thanks!