If you receive a warning while qualifying a DSL connection stating "Possible RIM detected in the area" - this means that the copper connection to the premises you have qualified may be running through a RIM before reaching the exchange.
You can learn more about RIM's in the Whirlpool Knowledge Base:
Please note that this is not a provider-specific error - this test relates to the copper cabling in the street running from the local exchange to the premises. This warning affects all connections of this type from all ISP's.
This qualification result is a warning only, you may still proceed with the connection if you accept the risks involved.