diff -r 1fec94e3df80 tools/libxl/xl_cmdimpl.c
--- a/tools/libxl/xl_cmdimpl.c  Fri Feb 11 13:26:50 2011 -0500
+++ b/tools/libxl/xl_cmdimpl.c  Fri Feb 11 13:41:14 2011 -0500
@@ -452,6 +452,8 @@ static int parse_disk_config(libxl_devic
     char *p, *end, *tok;

     memset(disk, 0, sizeof(*disk));
+    disk->format = DISK_FORMAT_RAW;
+    disk->backend = DISK_BACKEND_TAP;

     for(tok = p = buf2, end = buf2 + strlen(buf2) + 1; p < end; p++) {
         switch(state){
@@ -466,7 +468,8 @@ static int parse_disk_config(libxl_devic
                     state = DSTATE_PHYSPATH;
                     disk->format = DISK_FORMAT_RAW;
                     disk->backend = DISK_BACKEND_TAP;
-                }else if (!strcmp(tok, "tap")) {
+                }else if ((!strcmp(tok, "tap")) ||
+                          (!strcmp(tok, "tap2"))) {
                     state = DSTATE_TAP;
                 }else{
                     fprintf(stderr, "Unknown disk type: %s\n", tok);
@@ -485,9 +488,10 @@ static int parse_disk_config(libxl_devic
             if ( *p == ':' ) {
                 *p = '\0';
                 if (!strcmp(tok, "aio")) {
-                    disk->format = DISK_FORMAT_RAW;
-                    disk->backend = DISK_BACKEND_TAP;
-                }else if (!strcmp(tok, "vhd")) {
+                    tok = p + 1;
+                    break;
+                }
+                if (!strcmp(tok, "vhd")) {
                     disk->format = DISK_FORMAT_VHD;
                     disk->backend = DISK_BACKEND_TAP;
                 }else if (!strcmp(tok, "qcow")) {
@@ -496,7 +500,11 @@ static int parse_disk_config(libxl_devic
                 }else if (!strcmp(tok, "qcow2")) {
                     disk->format = DISK_FORMAT_QCOW2;
                     disk->backend = DISK_BACKEND_QDISK;
-                }else {
+                }else if (!strcmp(tok, "raw")) {
+                    disk->format = DISK_FORMAT_RAW;
+                    disk->backend = DISK_BACKEND_TAP;
+                }
+                else {
                     fprintf(stderr, "Unknown tapdisk type: %s\n", tok);
                     return 0;
                 }