CompactLogix as a Modbus slave AND master?

I have a CompactLogix L23E as a modbus slave being polled by another device (who is the master). However, now I need the L23E to read in values from other slaves. The current master doesn't have the ability to write.

I'm using the sample ModbusSlave.ACD file that came with RSLogix 5000 as my starting point. It doesn't look like I can cram the ModbusMaster into there, without potentially destroying the Slave, not to mention what it will do to the modbus network.

What are your suggestions for having the L23E act as a slave AND as a master, with another master on the network polling away. Sounds impossible to me. Am I correct?

I was going to recommend the Prosoft MVI69-MCM. It's compatable with other CompactLogix but I don't know about the L23E

For Modbus serial, you are limited to one master per physical serial network. It sounds like you need two serial interfaces, one for master and one for slave. Perhaps you should consider the Red Lion Data Station Plus protocol converter, and go Ethernet to your Compact Logix...
http://www.redlion.net/Products/HumanMachineInterface/DataStationPlus/DataStationPlus.html

Yeah, this project is out the door tomorrow, so hardware changes are not really possible. Was hoping for a software solution to this new request.