Connection Pool Timeout Error - .Net 4.0 Framework, Visual Studio 2010 VB Web Application

Question

Here is the error I am getting:
The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.
Here is what I am doing:
I have a VB.Net web application built on VS2010 and .Net Framework 4.0.
It accesses a SQL Server 2005 database. I am running this application on a IIS 6 web server in its own ApplicationPool. This is the Dev box. The database it is accessing (SQL 2005) is the production database. Eveything is fine on this server.
I want to move this application to the Production box, that is also runnning on IIS 6. When I acess the website runinig on the Production box, it runs for 5-10 minutes and then fails while accessing the database. It says the the connection pool has maxed out. When this happens, the site that is already running on the Dev Box and accessing the same SQL 2005 database keeps running without any issues. On the Production Box, if I reinstall or, restart website or recycle the pool it some times gets the site working again, but only for 5-10 minutes then it fails again.
The Production Box is new and this is the first .Net application running on this box. What's going on?