Why does this work fine
{% paginate craft.entries().limit(7).section('events').eventStartDate('>= ' ~ 2014 ~ '-' ~ 09) as entriesOnPage %}
But this does not
{% paginate craft.entries().limit(7).section('events').eventStartDate('>= ' ~ 2014 ~ '-' ~ 09) as entriesOnPage %}
I get this http://d.pr/i/NRvg
I also get errors when simply using '<' so it seems to require only either a less than or equal to or a greater than or equal to operator.
Can someone point to some kind of documentation for what is allowed within the custom field filter -------------> this part ('<= ' ~ 2014 ~ '-' ~ 09)