-DSYSV when building under SVR4.  This will not be set when 
using the
default configuration.  A quick fix is to add something like the
following to the client's Imakefile:
      #if SystemV4
           DEFINES = -DSYSV OTHER_CLIENT_DEPENDENT_DEFINES
      #endif
The best solution is to modify the code so it compiles correctly
without -DSYSV.