Well the BT-42 (according to my sources) didnt manage to knock out a T-34 by itself, but it was accompanied by a finnish jaegers who combined with the use of faustpatrone and BT's support took out a 76mm Sotka. But BT-42 itself didnt really knock out enemy tanks, instead it inflicted casualties to russian infantry who charged through the suburban outskirts of Viipuri towards finnish positions. Attack was reinforced by T-34-76's and KV-1's. A lone BT-42 started firing on enemy infantry to buy time for retreating finnish troops, but when the russian tanks started to make their movements towards the BT, it was decided to leave the place and enter deeper into Viipuri.
---
On other subjects, Eastern Front mod to COH is going to release its first public version on 21st of January '10.