Comment 7 for bug 1012184

> You have to add webkit_header attribute in your report xml tag (from 6.1).

how do i do that?

I tried it in the .xml file which is outside the report folder, it looks like this:

report_webkit_html_view.xml ---->
<?xml version="1.0" encoding="utf-8"?>
<openerp>
    <data>
        <report auto="False" id="invoice_report" model="account.invoice" name="webkit.invoice" string="Invoice Report" report_type="webkit" file="nt-sale/report/invoice_report_html.mako"/>
    </data>
</openerp>

but i get the following error:
     File "/usr/local/lib/python2.6/dist-packages/openerp-server/tools/convert.py", line 965, in convert_xml_import
    relaxng.assert_(doc)
  File "lxml.etree.pyx", line 2767, in lxml.etree._Validator.assert_ (src/lxml/lxml.etree.c:113500)
AssertionError: Invalid attribute webkit_header for element report, line 7