i assume you are using a Nokia Fixed Wireless Terminal connected to a trunk (Ring/Loop, TL11 or similar) on the MD110.
If this is so, then you should check the following:
1. Is the trunk looking for an Answer signal (polarity reversal) when the cellular call is connected - check in Route Category and Route Parameters (ROCAP & RODAP).
2. If the trunk route is set to look for an Answer, see if the FWT can provide this signal.
3. If the FWT cannot, then in Route Category and Route Parameters set the route for no Answer signal.