Thread:Extension talk:LDAP Authentication/search multiple OUs (Active Directory)

In our organization we have three OUs, all at the same branch level. Naturally I need to search (and match against users) in the first and send OU, but NOT the third.

So far, the following $wgLDAPSearchStrings config works for one OU:

So I tried:

Works for people in the "first" but not the "second". Are multi-valies recongnized in these arrays?