api chaining broken on rest (permission issue)

Been banging my head on a tricky one: I'm using the rest interface with the api_key of user 1, so I'm sure he has all the permissions needed.

I'm creating a contact with related entities (phone+addresses). The contact is properly created, but the related address isn't and I get a:

"Error in call to address_create : API permission check failed for address/create call; missing permission: access CiviCRM."

So it seems that the the current user is lost somewhere. When looking at the account->uid in user_access, it indeed seems to revert to user 0 somewhere between the contact creation and the related entity creation.

I tried to chain other apis and start with a different one that contact.create, when I chain phone.create as the main call and api.address.create it works! (I know it doens't make sense to chain these, but wanted to try)

I'm running low on ideas, someone got a suggestion?

P.S It's a regression from "not too long ago" (I'm sure it worked on 4.2), probably when we introduced better bootstrapping and acl in the api.

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