A corporate jet on a VOR/DME 27 Approach to PDK was advised by Tower of a low altitude alert. The flight crew checked their altimeters and procedure altitude and determined they were accurately flying the approach as charted.

Narrative

While en-route to PDK there was a light shower between us and the airport; so we elected to conduct the VOR/DME 27 Approach to PDK. The airport was reporting good VFR with the visibility 7 miles and the ceiling 2500 FT; but due to the light rain shower between us; we thought it best to do the approach. While leveling at the circling MDA with the airport in sight the Tower advised of a low altitude alert and gave us the current altimeter setting. We acknowledged it (our altimeters were set correctly and we never went below the circling MDA) and let them know we had the airport in sight. Nothing else was said about the warning and we proceeded to enter the right downwind to 2R as instructed and made a normal landing without incident. Afterwards I thought it might have been better to level off at a bit higher altitude knowing that the shower was well east of the airport and we had good weather at the airport for landing; but felt since we were cleared for the approach we should execute the approach as published.