7 businesses same address, only 1 shows up

On entering locations where there are many businesses in the same suite of offices, I discovered that only one business will show on the map. It seems whichever business is the most recent entry is the only one to show up.
For a client project I am adding 40 businesses to an SLP map and 7 of them have the same address.
How can I indicate there are multiple businesses at the address? Otherwise I will have one very happy client and 6 that are furious!

http://wordpress.org/plugins/store-locator-le/