A mailing machine is provided for processing mailpiece envelopes including a housing having a transport deck adapted to convey an envelope along a feed path and a receiving station. The mailing machine is reconfigurable to perform one of two mailpiece processing operations by alternately selecting or activating one of two mailpiece modules/assemblies. A first processing module/assembly is disposed along the feed path and is operative to moisten a glue line disposed along an envelope flap during the first mailpiece processing operation. The second processing module assembly is disposed along the feed path and is adapted to cut and open an edge of the envelope during the second mailpiece processing operation. Further, a mechanism for interchangeably receiving one of the first and second the processing modules/assemblies within the receiving station to perform the processing operations.