Tip 0728 discusses the 2048 open file per connection limit.

With Sp4, you can allow each terminal server client to maintain a separate virtual circuit.

Use regedt32 to navigate to:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Rdr\Parameters

Add Value name MultipleUsersOnConnection as a type REG_DWORD entry and set the data value to 0.