An XA-exploitive version of LISTSERV is now available. XA exploitation will be standard in version 1.8b, but is being made available now to customer who are storage constrained. In this first XA-exploitive release, the file I/O buffers must remain below the line because most versions of CMS do not support block I/O to locations above the line. Except for a few hundred kilobytes of data which must also remain below the line for compatibility with locally developed applications, all other data can be allocated above the line. A typical XA-exploitive LISTSERV session will have about 10M of free storage below the line, all of which can be used for file I/O buffers and file caching. If this still proves too restrictive, the file I/O routines will be modified to be truly XA-exploitive when running under a version of CMS which does allow block I/O above the line. Eric