Sub queries do not work properly in the on clause of a join

When subqueries are used in the on part of a join clause the Doctrine_Query_JoinCondition class does not always create the proper sql. For instance when there are 2 subqueries used in a between doctrine tries to parse the statement as 1 subquery rather 2 subqueries with an "and".

I will post my patch that fixes this issue after I make some test cases for it. I also fixed an issue where "(SQL:" syntax was breaking the join as well.

Will