Connection count gone wild after upgrade to SQL2k5!!!

Microsoft SQL Server

We upgraded our server last week to SQL 2005. Prior to this on SQL2k we
averaged 100 connections to the server from our web servers and in-house
applications. All we did was update our application config files so the
connection strings pointed at the new server and now we are up to over
5000!!!!! connections. All of our connection strings are either at the
default max connections or lowered to 50-75. We only have 2 web servers
hitting this SQL box and probably a couple dozen workstations running
windows apps in a very subdued manner, i.e. not db intensive at all.

How could this happen? I'm tempted to alter the server config and force a
max# connections but I'm worried what will happen if I do.

Any input/ideas???
How do you count the number of connections?
Perfmon - SQLServer:General Statistics -> User Connections
Are you using Service Broker activation by any chance? This would include
also features like SqlDependency or Web pages SqlCacheDependency that are
using activation behind the scenes. Activation can cause the perf counter to
go to abnormaly high values, but is only a perfcounter issue (is not
decremented properly).

You can confirm if the connections really grow or is just the a counter
problem by using a management view, like sys.dm_exec_connections.