Antenna Problems...Apartment Complexes

I've been helping a few people getting their DTV converter boxes working with their TVs. Two people in large apartment/condo complexes tried to connect the DTV converter box to the internal TV outlet and when they do a channel scan they get nothing or just a couple channels. Today I was assisting a person in a large apartment complex that was having a hair pulling problem with his DTV converter box. With the TV connected to the internal system (cable outlet on the wall) analog TV reception was excellent. However when I tried to do a channel scan on the DTV converter box connected to the internal cable, we got only 2 channels coming from one station, we should be getting 45 channels. I connected a set of rabbit ears to the input of converter box and did another scan. Now we got 15+ channels. The problem with these large apartment/condo complexes is they have a central antenna that receives individual channels, e.g. 2, 4, 5, 7, 9, 36, 54 and then amplifies these signals to all the apartment units. They don't have an amplifier that retransmits channels 2 through 69. What this means is that all the digital channels are left out, no signal. The only way around this is to either talk to the apartment/condo management people or go around them and install your own antenna. Has anyone else had the same experience.