diff --git a/src/nwvolume.c b/src/nwvolume.c
index dfe0305..b56cd17 100644
--- a/src/nwvolume.c
+++ b/src/nwvolume.c
@@ -938,9 +938,14 @@ const char *find_device_file(const char *path)
 /* Modern glibc declares quotactl() in <sys/quota.h>.  The old _syscall4()
  * wrapper no longer builds on current systems, so do not provide a private
  * syscall stub here.
+ *
+ * Prefer Q_SETQUOTA when available.  Q_SETQLIM can fail with ESRCH when no
+ * dquot record exists yet; Q_SETQUOTA is the modern "write this dqblk" API.
  */
-# if !defined(Q_SETQLIM) && defined(Q_SETQUOTA)
-#  define Q_SETQLIM Q_SETQUOTA
+# if defined(Q_SETQUOTA)
+#  define MARS_Q_SETQUOTA Q_SETQUOTA
+# elif defined(Q_SETQLIM)
+#  define MARS_Q_SETQUOTA Q_SETQLIM
 # endif
 #endif /* LINUX */
 
@@ -1019,7 +1024,7 @@ int nw_set_vol_restrictions(uint8 volnr, int uid, uint32 quota)
 	    dqblk.dqb_ihardlimit,
 	    dqblk.dqb_curinodes));
 
-  res=su_quotactl(QCMD(Q_SETQLIM, USRQUOTA), device, uid, (caddr_t) &dqblk);
+  res=su_quotactl(QCMD(MARS_Q_SETQUOTA, USRQUOTA), device, uid, (caddr_t) &dqblk);
   if (res != 0) {
     XDPRINTF((2,0, "Set quota failed device=%s uid=%d quota=%dK errno=%d",
               device, uid, quota, errno));