There is a way to set it but you will need to edit the following files:
./atlassian-jira/secure/views/navigator/navigator-excel.jsp
./atlassian-jira/secure/views/navigator/navigator-excel-current.jsp
You will need to edit them so that the top of the produced html file looks like:
<html xmlns:o="urn:schemas-microsoft-com:office:office"
xmlns:x="urn:schemas-microsoft-com:office:excel"
xmlns="http://www.w3.org/TR/REC-html40">
<head>
<title>JIRA Issue Navigator for Excel (All)</title>
<META HTTP-EQUIV="Content-Type" Content="application/vnd.ms-excel; charset=utf-8">
<style>
@page
{
mso-page-orientation:landscape;
margin:.25in .25in .5in .25in;
mso-header-margin:.5in;
mso-footer-margin:.25in;
mso-footer-data:"&R&P of &N";
mso-horizontal-page-align:center;
mso-vertical-page-align:center;
}
</style>
<!--[if gte mso 9]><xml>
<x:ExcelWorkbook>
<x:ExcelWorksheets>
<x:ExcelWorksheet>
<x:Name>general_report</x:Name>
<x:WorksheetOptions>
<x:Print>
<x:ValidPrinterInfo/>
</x:Print>
</x:WorksheetOptions>
</x:ExcelWorksheet>
</x:ExcelWorksheets>
</x:ExcelWorkbook>
</xml><![endif]-->
</head>
Cheers,
Nick
Added this header to the jsp that generates the excel file. This works for excel, the default print type is landscape. This does not seem to work for OpenOffice, but since we don't explicitly support that it is not a big deal.