TNG4* - Retrieving parked calls charged

[hnsmith]

I am running TNG for Asterisk and we use the Parking feature of Asterisk (transfer a call to extension 700, call gets placed in a holding area <extension 701, 702, 703, etc.>).
When retrieving a call from the parking area by dialling 701 for instance, that call shows up in TNG as "2721701 BERGVLIET - (ZA)" and carries a cost instead of showing 0.
How can I prevent this from happening?