How to manage the pool of connections or connections?

The problem:

I have a user to connect the rails application to the database. This
user has the limitation of using a single connection to the database.
The application works fine but with evidence of some forms that perform
multiple queries (with many screen refreshes at a time) to sail several
different sessions open and I get the error "Too many connections to
Role xxxx. " The error is in the database so the application does not
control.

I do not understand much of the pool of connections but I have a
hypothesis that as there are so many connections in the pool reaches a
limit you want to do a new pool (new connection application) and that’s
where I get the problem.

The setting:

Ruby 1.8.6
Rails 2.3.9
Apache + Passenger
Authloghic + + Rpam AuthlogicPam

As I can solve this problem?

Thanks in advance!