Why does my UUID column result in a "Bad Base64 Input Character" with DBUnit?

Question

I have a Hibernate DAO class with a UUID column, works fine when i run it on my server against mySQL. However, i am trying to write an integration test using DBUnit, and i get a strange error message:

"Bad Base64 input character at 4: 39(decimal)"

Java class:

@Column
private UUID uuid;

DBUnit XML:

<object uuid="uuid'789446f8-3683-11e9-8f19-acde48001122'" languageenum="1"....

If i change the column from UUID to String, it all works swimmingly. I have read the DBUnit docs, and this is how i think you define it in XML. Not sure where to look, so pointers are much appreciated.

DBUnit 2.6.1