diff --git a/hw/boards.h b/hw/boards.h
index f6733b7..5a07d07 100644
--- a/hw/boards.h
+++ b/hw/boards.h
@@ -17,6 +17,7 @@ typedef struct QEMUMachine {
     int use_scsi;
     int max_cpus;
     int is_default;
+    struct CompatProperty *compat_props;
     struct QEMUMachine *next;
 } QEMUMachine;
 
diff --git a/hw/pc.c b/hw/pc.c
index 38678da..cd64ccf 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -1460,6 +1460,21 @@ static QEMUMachine pc_machine = {
     .is_default = 1,
 };
 
+static QEMUMachine pc_machine_v0_10 = {
+    .name = "pc-0.10",
+    .desc = "Standard PC, qemu 0.10",
+    .init = pc_init_pci,
+    .max_cpus = 255,
+    .compat_props = (CompatProperty[]) {
+        {
+            .driver   = "virtio-blk-pci",
+            .property = "class",
+            .value    = "0x0180", /* PCI_CLASS_STORAGE_OTHER */
+        },
+        { /* end of list */ }
+    },
+};
+
 static QEMUMachine isapc_machine = {
     .name = "isapc",
     .desc = "ISA-only PC",
@@ -1470,6 +1485,7 @@ static QEMUMachine isapc_machine = {
 static void pc_machine_init(void)
 {
     qemu_register_machine(&pc_machine);
+    qemu_register_machine(&pc_machine_v0_10);
     qemu_register_machine(&isapc_machine);
 }
 
diff --git a/hw/qdev-properties.c b/hw/qdev-properties.c
index 720001b..bec756d 100644
--- a/hw/qdev-properties.c
+++ b/hw/qdev-properties.c
@@ -228,3 +228,22 @@ void qdev_prop_set_defaults(DeviceState *dev, Property *props)
     }
 }
 
+static CompatProperty *compat_props;
+
+void qdev_register_compat_props(CompatProperty *props)
+{
+    compat_props = props;
+}
+
+void qdev_prop_set_compat(DeviceState *dev)
+{
+    CompatProperty *prop;
+
+    if (!compat_props)
+        return;
+    for (prop = compat_props; prop->driver != NULL; prop++) {
+        if (strcmp(dev->info->name, prop->driver) != 0)
+            continue;
+        qdev_prop_parse(dev, prop->property, prop->value);
+    }
+}
diff --git a/hw/qdev.c b/hw/qdev.c
index 9f7ac0b..ebb6bcf 100644
--- a/hw/qdev.c
+++ b/hw/qdev.c
@@ -130,6 +130,7 @@ DeviceState *qdev_create(BusState *bus, const char *name)
     dev->parent_bus = bus;
     qdev_prop_set_defaults(dev, dev->info->props);
     qdev_prop_set_defaults(dev, dev->parent_bus->info->props);
+    qdev_prop_set_compat(dev);
     LIST_INSERT_HEAD(&bus->children, dev, sibling);
     return dev;
 }
diff --git a/hw/qdev.h b/hw/qdev.h
index be10f44..5b4c1b0 100644
--- a/hw/qdev.h
+++ b/hw/qdev.h
@@ -8,6 +8,8 @@ typedef struct Property Property;
 
 typedef struct PropertyInfo PropertyInfo;
 
+typedef struct CompatProperty CompatProperty;
+
 typedef struct DeviceInfo DeviceInfo;
 
 typedef struct BusState BusState;
@@ -63,6 +65,12 @@ struct PropertyInfo {
     int (*print)(DeviceState *dev, Property *prop, char *dest, size_t len);
 };
 
+struct CompatProperty {
+    const char *driver;
+    const char *property;
+    const char *value;
+};
+
 /*** Board API.  This should go away once we have a machine config file.  ***/
 
 DeviceState *qdev_create(BusState *bus, const char *name);
@@ -152,4 +160,7 @@ int qdev_prop_set_uint32(DeviceState *dev, const char *name, uint32_t value);
 int qdev_prop_set_ptr(DeviceState *dev, const char *name, void *value);
 void qdev_prop_set_defaults(DeviceState *dev, Property *props);
 
+void qdev_register_compat_props(CompatProperty *props);
+void qdev_prop_set_compat(DeviceState *dev);
+
 #endif
diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index 96f3764..996dadb 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -87,12 +87,7 @@ typedef struct {
     VirtIODevice *vdev;
     uint32_t addr;
 
-    uint16_t vendor;
-    uint16_t device;
-    uint16_t subvendor;
-    uint16_t class_code;
-    uint8_t pif;
-
+    uint32_t class_code;
     qname hostlink;
 } VirtIOPCIProxy;
 
@@ -421,12 +416,15 @@ static void virtio_blk_init_pci(PCIDevice *pci_dev)
     VirtIOPCIProxy *proxy = DO_UPCAST(VirtIOPCIProxy, pci_dev, pci_dev);
     VirtIODevice *vdev;
 
+    if (proxy->class_code != PCI_CLASS_STORAGE_SCSI &&
+        proxy->class_code != PCI_CLASS_STORAGE_OTHER)
+        proxy->class_code = PCI_CLASS_STORAGE_SCSI;
+
     vdev = virtio_blk_init(&pci_dev->qdev, proxy->hostlink);
     virtio_init_pci(proxy, vdev,
                     PCI_VENDOR_ID_REDHAT_QUMRANET,
                     PCI_DEVICE_ID_VIRTIO_BLOCK,
-                    PCI_CLASS_STORAGE_OTHER,
-                    0x00);
+                    proxy->class_code, 0x00);
 }
 
 static void virtio_console_init_pci(PCIDevice *pci_dev)
@@ -478,6 +476,10 @@ static PCIDeviceInfo virtio_info[] = {
                 .name   = "drive",
                 .info   = &qdev_prop_name,
                 .offset = offsetof(VirtIOPCIProxy, hostlink),
+            },{
+                .name   = "class",
+                .info   = &qdev_prop_hex32,
+                .offset = offsetof(VirtIOPCIProxy, class_code),
             },
             {/* end of list */}
         },
diff --git a/vl.c b/vl.c
index 0acc1de..2c5608f 100644
--- a/vl.c
+++ b/vl.c
@@ -6030,6 +6030,8 @@ int main(int argc, char **argv, char **envp)
 
     module_call_init(MODULE_INIT_DEVICE);
 
+    if (machine->compat_props)
+        qdev_register_compat_props(machine->compat_props);
     machine->init(ram_size, boot_devices,
                   kernel_filename, kernel_cmdline, initrd_filename, cpu_model);