Using locales with a dash instead of an underscore

[jrmyio]

In my app there I have 3 locales
en, nl-nl and nl-be.

I defined the odm locales as:

doctrine_phpcr:
    odm:
        locales:
            en: [nl-nl, nl-be]
            nl-nl : [nl-be, en]
            nl-be : [nl-nl, en]

However, this dashes used in this configuration seem to be overwritten by PHPCR to underscore.

As soon as I go to the Admin Bundle
admin/cmf/block/simpleblock/cms/blocks/test/edit?tl=nl-nl

I will hit an error `There is no language fallback for language 'nl-nl'.

Is this a problem of the PHPCR-admin-integration that it has to also overwrite dashes with underscores or shouldn't this be happening in the first place?

Is there any solution to tackle this problem without having locales to be using underscores?

[dbu]

i don't know where exactly this happens, but looking at the symfony translation component for example, it seems that symfony is rather opinionated about using underscore to separate the locale parts. i don't think this bundle does anything about handling locales. either it could be in phpcr-odm, the phpcr bundle or even in core symfony. if you can find where it happens, i am happy to fix it in phpcr-odm. if its inside symfony itself i guess we are out of luck however.