Sunspot/Solr: non-alphabetical characters
===

I'm using Solr with Sunspot/dismax. Is it possible to query for non-alphabetic characters? I.e.: 

`~ ! @ # $ % ^ & * ( ) _ + - = [ ] { } | \`

I'm aware that `+/-` must be escaped, as they are dismax inclusion/exclusion operators. But I'm getting no matches when I search for any of these characters:

    Foo.search { fulltext '=' }.results.length   # => 0
    Foo.search { fulltext '\=' }.results.length  # => 0

Yet: 

    Foo.search { fulltext 'a'}.results.length    # => 30




