diff --git a/bindings/dotnet/src/Sigar.cs b/bindings/dotnet/src/Sigar.cs
index 8cf50eaf..533d85f6 100644
--- a/bindings/dotnet/src/Sigar.cs
+++ b/bindings/dotnet/src/Sigar.cs
@@ -203,6 +203,7 @@ namespace Hyperic.Sigar {
         public readonly ulong Sys;
         private readonly ulong NA_Nice;
         public readonly ulong Idle;
+        private readonly ulong NA_Wait;
         public readonly ulong Total;
 
         [DllImport(Sigar.LIBSIGAR)]
diff --git a/bindings/java/src/jni/generate.pl b/bindings/java/src/jni/generate.pl
index 689a0ff2..92522beb 100644
--- a/bindings/java/src/jni/generate.pl
+++ b/bindings/java/src/jni/generate.pl
@@ -194,6 +194,11 @@ my %classes = (
          desc => 'Total system cpu idle time',
          plat => '*'
       },
+      {
+         name => 'wait', type => 'Long',
+         desc => 'Total system cpu io wait time',
+         plat => 'ALHS'
+      },
       {
          name => 'total', type => 'Long',
          desc => 'Total system cpu time',
diff --git a/bindings/java/src/net/hyperic/sigar/test/TestCpu.java b/bindings/java/src/net/hyperic/sigar/test/TestCpu.java
index 1d33b2b6..3068229f 100644
--- a/bindings/java/src/net/hyperic/sigar/test/TestCpu.java
+++ b/bindings/java/src/net/hyperic/sigar/test/TestCpu.java
@@ -21,6 +21,9 @@ public class TestCpu extends SigarTestCase {
         traceln("Idle=" + cpu.getIdle());
         assertTrue(cpu.getIdle() >= 0);
 
+        traceln("Wait=" + cpu.getWait());
+        assertTrue(cpu.getWait() >= 0);
+
         traceln("Total=" + cpu.getTotal());
         assertTrue(cpu.getTotal() >= 0);
     }
diff --git a/include/sigar.h b/include/sigar.h
index 128e5ded..a0ee2165 100644
--- a/include/sigar.h
+++ b/include/sigar.h
@@ -96,6 +96,7 @@ typedef struct {
         sys,
         nice,
         idle,
+        wait,
         total;
 } sigar_cpu_t;
 
diff --git a/src/os/aix/aix_sigar.c b/src/os/aix/aix_sigar.c
index d16e5e9d..cb4e4fb6 100644
--- a/src/os/aix/aix_sigar.c
+++ b/src/os/aix/aix_sigar.c
@@ -579,7 +579,8 @@ int sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
             cpu->nice  = -1; /* N/A */
             cpu->sys   = cpu_data.sys;
             cpu->idle  = cpu_data.idle;
-            cpu->total = cpu->user + cpu->sys + cpu->idle + cpu_data.wait;
+            cpu->wait  = cpu_data.wait;
+            cpu->total = cpu->user + cpu->sys + cpu->idle + cpu->wait;
             return SIGAR_OK;
         }
     }
@@ -702,7 +703,8 @@ static int sigar_cpu_list_get_pstat(sigar_t *sigar, sigar_cpu_list_t *cpulist)
             cpu->nice  = -1; /* N/A */
             cpu->sys   = data.sys;
             cpu->idle  = data.idle;
-            cpu->total = cpu->user + cpu->sys + cpu->idle + data.wait;
+            cpu->wait  = data.wait;
+            cpu->total = cpu->user + cpu->sys + cpu->idle + cpu->wait;
         }
         else {
             sigar_log_printf(sigar, SIGAR_LOG_ERROR,
diff --git a/src/os/darwin/darwin_sigar.c b/src/os/darwin/darwin_sigar.c
index 1fcaa5f0..9e6b7663 100644
--- a/src/os/darwin/darwin_sigar.c
+++ b/src/os/darwin/darwin_sigar.c
@@ -220,7 +220,7 @@ int sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
     cpu->sys  = cpuload.cpu_ticks[CPU_STATE_SYSTEM];
     cpu->idle = cpuload.cpu_ticks[CPU_STATE_IDLE];
     cpu->nice = cpuload.cpu_ticks[CPU_STATE_NICE];
-
+    cpu->wait = 0; /*N/A*/
     cpu->total = cpu->user + cpu->nice + cpu->sys + cpu->idle;
 
 #else
@@ -229,7 +229,7 @@ int sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
     cpu->nice = 0;
     cpu->sys  = 0;
     cpu->idle = 0;
-
+    cpu->wait = 0; /*N/A*/
     cpu->total = cpu->user + cpu->nice + cpu->sys + cpu->idle;
 #endif
 
diff --git a/src/os/hpux/hpux_sigar.c b/src/os/hpux/hpux_sigar.c
index 4ee5cd60..5dbeecf3 100644
--- a/src/os/hpux/hpux_sigar.c
+++ b/src/os/hpux/hpux_sigar.c
@@ -98,6 +98,7 @@ int sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
     cpu->sys  = stats.psd_cpu_time[CP_SYS] + stats.psd_cpu_time[CP_SSYS];
     cpu->nice = stats.psd_cpu_time[CP_NICE];
     cpu->idle = stats.psd_cpu_time[CP_IDLE];
+    cpu->wait = stats.psd_cpu_time[CP_WAIT];
     
     cpu->total = 0;
     
@@ -136,6 +137,7 @@ int sigar_cpu_list_get(sigar_t *sigar, sigar_cpu_list_t *cpulist)
         cpu->sys  = proc.psp_cpu_time[CP_SYS] + proc.psp_cpu_time[CP_SSYS];
         cpu->nice = proc.psp_cpu_time[CP_NICE];
         cpu->idle = proc.psp_cpu_time[CP_IDLE];
+        cpu->wait = proc.psp_cpu_time[CP_WAIT];
 
         cpu->total = 0;
 
diff --git a/src/os/linux/linux_sigar.c b/src/os/linux/linux_sigar.c
index 9860fb60..72415984 100644
--- a/src/os/linux/linux_sigar.c
+++ b/src/os/linux/linux_sigar.c
@@ -292,8 +292,8 @@ static void get_cpu_metrics(sigar_cpu_t *cpu, char *line)
     cpu->nice += sigar_strtoul(ptr);
     cpu->sys  += sigar_strtoul(ptr);
     cpu->idle += sigar_strtoul(ptr);
-
-    cpu->total += cpu->user + cpu->nice + cpu->sys + cpu->idle;
+    cpu->wait = 0; /*XXX*/
+    cpu->total += cpu->user + cpu->nice + cpu->sys + cpu->idle + cpu->wait;
 }
 
 int sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
diff --git a/src/os/osf1/osf1_sigar.c b/src/os/osf1/osf1_sigar.c
index 5073d67a..c15409b1 100644
--- a/src/os/osf1/osf1_sigar.c
+++ b/src/os/osf1/osf1_sigar.c
@@ -85,8 +85,8 @@ int sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
     cpu->nice = sysinfo.si_nice;
     cpu->sys  = sysinfo.si_sys;
     cpu->idle = sysinfo.si_idle;
-
-    cpu->total = cpu->user + cpu->nice + cpu->sys + cpu->idle;
+    cpu->wait = 0; /*N/A?*/
+    cpu->total = cpu->user + cpu->nice + cpu->sys + cpu->idle + cpu->wait;
 
     return SIGAR_OK;
 }
diff --git a/src/os/solaris/solaris_sigar.c b/src/os/solaris/solaris_sigar.c
index 3d977386..4b2dbca4 100644
--- a/src/os/solaris/solaris_sigar.c
+++ b/src/os/solaris/solaris_sigar.c
@@ -291,6 +291,7 @@ int sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
         cpu->sys   += xcpu->sys;
         cpu->idle  += xcpu->idle;
         cpu->nice  += xcpu->nice;
+        cpu->wait  += xcpu->wait;
         cpu->total += xcpu->total;
     }
 
@@ -358,6 +359,7 @@ int sigar_cpu_list_get(sigar_t *sigar, sigar_cpu_list_t *cpulist)
         cpu->user = cpuinfo[CPU_USER];
         cpu->sys  = cpuinfo[CPU_KERNEL];
         cpu->idle = cpuinfo[CPU_IDLE];
+        cpu->wait = cpuinfo[CPU_WAIT];
         cpu->nice = 0; /* no cpu->nice */
         cpu->total = 0;
 
diff --git a/src/os/stub/stub_sigar.c b/src/os/stub/stub_sigar.c
index ffd787a0..58334b68 100644
--- a/src/os/stub/stub_sigar.c
+++ b/src/os/stub/stub_sigar.c
@@ -48,6 +48,7 @@ int sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
     cpu->nice = -1;
     cpu->sys  = -1;
     cpu->idle = -1;
+    cpu->wait = -1;
 
     cpu->total = cpu->user + cpu->nice + cpu->sys + cpu->idle;
 
diff --git a/src/os/win32/win32_sigar.c b/src/os/win32/win32_sigar.c
index ac19cf91..848b4210 100644
--- a/src/os/win32/win32_sigar.c
+++ b/src/os/win32/win32_sigar.c
@@ -413,8 +413,8 @@ SIGAR_DECLARE(int) sigar_cpu_get(sigar_t *sigar, sigar_cpu_t *cpu)
     cpu->user = PERF_VAL(PERF_IX_CPU_USER);
     status = get_idle_cpu(sigar, cpu, -1, counter_block, perf_offsets);
     cpu->nice = 0; /* no nice here */
-
-    cpu->total = cpu->sys + cpu->user + cpu->idle;
+    cpu->wait = 0; /*N/A?*/
+    cpu->total = cpu->sys + cpu->user + cpu->idle + cpu->wait;
 
     if (status != SIGAR_OK) {
         sigar_log_printf(sigar, SIGAR_LOG_WARN,