[Update: Telcontar now calls itself deCarta]. In a press release like format Sys-Con Australia describes the Open API for Telcontar Drill Down Server (and not Telecontar). Telcontar as published here has among its clients "Google, Yahoo, Rand McNally and AskJeeves. It supplies geocoding, routing, spatial search plus traffic data for road conditions and detours."
Telcontar is also making available hosted web services that according to SymbianOne is:
[..] industry's most advanced and easy-to-use solution for creating rich, high-performance AJAX fluid maps for location-enabled applications.