IdP v3 not releasing attributes to SAML1 SPs

[Mark K. Miller]

Today's clueless Shibboleth IdP v3 question from Max:

So far, I've only searched the v3 wiki for "SAML1" and I'm not getting 
much in the way of search results.

I've had a few more reports today of SPs not working.  The first thing 
I've noticed in the idp-process.log is that these SP are all still using 
SAML1.  It appears that the authentication happens without issue, but I'm 
not seeing any attributes get sent to these SAML1 SPs.

Is this something that's know to break in the v2-to-v3 upgrade?  Can 
anyone provide a pointer to some v3 IdP config that would get these SP 
working again (cause my IdP to release the attributes?)

Any other advice?

Thanks,

Max