OpenOffice 4.0.1 / Problem with xlsx file

[INDAG GmbH & Co Betriebs KG]

Hallo,

we are using OpenOffice 4.0.1

With Calc we can open xlsx files generated by Excel 2010.

But when we generate a xlsx file with TIA Portal from Siemens, we cannot open 
it with OpenOffice.
It works with Excel 2010.

Thank you for any advice.