: are you using either dismax or edismax? They don't respect : the defaultOperator. Use the mm param to get this kind : of behavior.
FWIW: that has not been tru since Solr 3.1 ... mm's default value is now based on q.op (which get's it's default from defaultOperator in the schema.xml) By Erick's point is still valid: we need all the details of the request you are executing, and what the request handler config looks like, and what the debugQuery output for that request lookse like, etc. before we can make a guess as to why you are getting the results you are getting. -Hoss
