Libreoffice re-type password

I’m using Libreoffice 4.1 and when I save my ODS spreadsheet with many password protected sheets to an excel file I have to Re-type passwords for every sheet.

The error displayed is ‘Hash incompatible’ and it’s not on every sheet. This problem only seems to be with old files, if I try and recreate it with a new file from scratch it doesn’t work.