diff --git a/Chap_API_Server.tex b/Chap_API_Server.tex
index cfbede8..e5d2752 100644
--- a/Chap_API_Server.tex
+++ b/Chap_API_Server.tex
@@ -4193,7 +4193,7 @@ \subsubsection{IOF delivery function}
 \begin{codepar}
 typedef void (*pmix_iof_cbfunc_t)(
                     size_t iofhdlr, pmix_iof_channel_t channel,
-                    pmix_proc_t *source, char *payload,
+                    pmix_proc_t *source, pmix_byte_object_t *payload,
                     pmix_info_t info[], size_t ninfo);
 \end{codepar}
 \cspecificend
@@ -4202,7 +4202,7 @@ \subsubsection{IOF delivery function}
 \argin{iofhdlr}{Registration number of the handler being invoked (\code{size_t})}
 \argin{channel}{bitmask identifying the channel the data arrived on (\refstruct{pmix_iof_channel_t})}
 \argin{source}{Pointer to a \refstruct{pmix_proc_t} identifying the namespace/rank of the process that generated the data (\code{char*})}
-\argin{payload}{Pointer to character array containing the data.}
+\argin{payload}{Pointer to a \refstruct{pmix_byte_object_t} that describes the character array containing the data.}
 \argin{info}{Array of \refstruct{pmix_info_t} provided by the source containing metadata about the payload. This could include \refattr{PMIX_IOF_COMPLETE} (handle)}
 \argin{ninfo}{Number of elements in \refarg{info} (\code{size_t})}
 \end{arglist}