-The parameters B<pkey> and B<cert> cannot be B<NULL>. B<ca> can be <NULL> in
-which case additional certificates will be discarded. B<*ca> can also be a
-valid STACK in which case additional certificates are appended to B<*ca>. If
-B<*ca> is B<NULL> a new STACK will be allocated.
+Each of the parameters B<pkey>, B<cert>, and B<ca> can be NULL in which case
+the private key, the corresponding certificate, or the additional certificates,
+respectively, will be discarded.
+If any of B<pkey> and B<cert> is non-NULL the variable it points to is
+initialized.
+If B<ca> is non-NULL and B<*ca> is NULL a new STACK will be allocated.
+If B<ca> is non-NULL and B<*ca> is a valid STACK
+then additional certificates are appended in the given order to B<*ca>.