Fix a problem reported on the user list by Teng Lin: OPAL_PREFIX

wasn't exported in the Bourne-shell-flavor case on remote nodes.

This commit was SVN r19770.

orte/mca/plm/rsh/plm_rsh_module.c

@@ -553,7 +553,7 @@ static int setup_launch(int *argcptr, char ***argvptr,
                       "%s %s/%s/%s",
                       (opal_prefix != NULL ? "OPAL_PREFIX=" : ""),
                       (opal_prefix != NULL ? opal_prefix : ""),
-                      (opal_prefix != NULL ? " ;" : ""),
+                      (opal_prefix != NULL ? " ; export OPAL_PREFIX;" : ""),
                       prefix_dir, bin_base,
                       prefix_dir, lib_base,
                       (orted_prefix != NULL ? orted_prefix : ""),