Magma on 3.10

Hi, I just installed magma on a squeak-dev image (from Damien Cassou) based on build 7159 (latest 3.10 image)

I load packages "magma client 1.0 (r40)", "magma server 1.0 (r40)" and "magma tester 1.0 (r40)" from universes and executed first "getting started" code, with a very simple modification:

MagmaRepositoryController create: (FileDirectory default directoryNamed: 'repository') fullName root: Dictionary new

executing this code throws a doesNotUnderstood: #open on ByteString. The message call comes from MaFileStreamPool>>renewAccess:

Same code executed on a 3.9 image (from Damien Cassou, too) works fine. Is there a possible solution for this? i really need to run magma on 3.10 images.

Thanks, Esteban