Does not work together with ImportExportModelAdmin

[milossramek]

Hi,
The Totals line does not display if the class derives also from ImportExportModelAdmin:
This is OK:
class TransakciaAdmin(SimpleHistoryAdmin, TotalsumAdmin):
This does not work:
class TransakciaAdmin(SimpleHistoryAdmin, ImportExportModelAdmin, TotalsumAdmin):

In the second case the templates totalsum_change_list.html and totalsum_change_list_results.html are not called at all.