diff -Naur xfce4-diskperf-plugin-2.2.0~/panel-plugin/main.c xfce4-diskperf-plugin-2.2.0/panel-plugin/main.c
--- xfce4-diskperf-plugin-2.2.0~/panel-plugin/main.c	2008-04-17 09:11:23.000000000 +0200
+++ xfce4-diskperf-plugin-2.2.0/panel-plugin/main.c	2010-07-26 17:55:16.179327437 +0200
@@ -148,6 +148,7 @@
     struct param_t *poConf = &(p_poPlugin->oConf.oParam);
     struct monitor_t *poMonitor = &(p_poPlugin->oMonitor);
     struct perfbar_t *poPerf = poMonitor->aoPerfBar;
+    struct stat     oStat;
     uint64_t        iInterval_ns, rbytes, wbytes, iRBusy_ns, iWBusy_ns;
     const double    K = 1.0 * 1000 * 1000 * 1000 / 1024 / 1024;
     /* bytes/ns --> MB/s */
@@ -164,6 +165,8 @@
 #if defined (__NetBSD__) || defined(__OpenBSD__)
     status = DevGetPerfData (poConf->acDevice, &oPerf);
 #else
+	if (stat (poConf->acDevice, &oStat) != -1)
+		poConf->st_rdev = oStat.st_rdev;
     status = DevGetPerfData (&(poConf->st_rdev), &oPerf);
 #endif
     if (status == -1)