T29G + EXP20 dont display similar output

[chidado]

Hello,
We have a T29G and EXP20 setup with a custom DSSKey. When we program the custom DSS key, the label varies from the phone to the expansion module.

firmware for phone is 46.81.0.25.
firmware for expansion module is 9.16.0.0

The Line Key Type is Custom, value is $KLineKey2$*97$Cwc$$Cp3$1234$Tdtmf$ and Label is VM. If we choose Line key that will display label on the phone it will display properly if we choose the EXT key the display garbled alon with VM at the end.

Thanks in advance