diff --git a/block/vmdk.c b/block/vmdk.c
index 872aeba..4dfca58 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -43,19 +43,27 @@ typedef struct {
     uint32_t sectors_per_track;
 } VMDK3Header;
 
+typedef uint8_t Bool;
+typedef uint64_t SectorType;
+
 typedef struct {
     uint32_t version;
     uint32_t flags;
-    int64_t capacity;
-    int64_t granularity;
-    int64_t desc_offset;
-    int64_t desc_size;
-    int32_t num_gtes_per_gte;
-    int64_t rgd_offset;
-    int64_t gd_offset;
-    int64_t grain_offset;
-    char filler[1];
-    char check_bytes[4];
+    SectorType capacity;
+    SectorType granularity;
+    SectorType desc_offset;
+    SectorType desc_size;
+    uint32_t num_gtes_per_gte;
+    SectorType rgd_offset;
+    SectorType gd_offset;
+    SectorType grain_offset;
+    Bool uncleanshutdown;
+    char singlendlinechar;
+    char nonendlinechar;
+    char doublendlinechar1;
+    char doublendlinechar2;
+    uint16_t   compressAlgorithm;
+    uint8_t  pad[433];
 } __attribute__((packed)) VMDK4Header;
 
 #define L2_CACHE_SIZE 16
@@ -364,6 +372,10 @@ static int vmdk_open(BlockDriverState *bs, int flags)
     BDRVVmdkState *s = bs->opaque;
     uint32_t magic;
     int l1_size, i;
+    u_int64_t GD_AT_END = 0xffffffffffffffff;
+    struct stat sb;
+    uint32_t ret;
+	
 
     if (bdrv_pread(bs->file, 0, &magic, sizeof(magic)) != sizeof(magic))
         goto fail;
@@ -386,6 +398,19 @@ static int vmdk_open(BlockDriverState *bs, int flags)
 
         if (bdrv_pread(bs->file, sizeof(magic), &header, sizeof(header)) != sizeof(header))
             goto fail;
+		if (le64_to_cpu(header.gd_offset) == GD_AT_END) {
+			uint64_t filesize;
+			if (stat(bs->filename, &sb) == -1) {
+				fprintf(stderr, "Unable to get file size.\n");
+			return -1;
+			}
+
+		filesize = (((uint64_t)sb.st_size + (512 - 1)) & ~(uint64_t)(512 - 1));
+		ret = bdrv_pread(bs->file, (filesize - 1024 + sizeof(magic)), &header, sizeof(header));
+			if (ret != sizeof(header)) {
+				return ret;
+			}
+		}	
         bs->total_sectors = le64_to_cpu(header.capacity);
         s->cluster_sectors = le64_to_cpu(header.granularity);
         s->l2_size = le32_to_cpu(header.num_gtes_per_gte);
@@ -395,8 +420,7 @@ static int vmdk_open(BlockDriverState *bs, int flags)
         s->l1_size = (bs->total_sectors + s->l1_entry_sectors - 1)
             / s->l1_entry_sectors;
         s->l1_table_offset = le64_to_cpu(header.rgd_offset) << 9;
-        s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
-
+       	s->l1_backup_table_offset = le64_to_cpu(header.gd_offset) << 9;
         // try to open parent images, if exist
         if (vmdk_parent_open(bs) != 0)
             goto fail;
@@ -424,6 +448,7 @@ static int vmdk_open(BlockDriverState *bs, int flags)
         }
     }
 
+
     s->l2_cache = qemu_malloc(s->l2_size * L2_CACHE_SIZE * sizeof(uint32_t));
     return 0;
  fail:
@@ -743,11 +768,11 @@ static int vmdk_create(const char *filename, QEMUOptionParameter *options)
     header.gd_offset = cpu_to_le64(header.gd_offset);
     header.grain_offset = cpu_to_le64(header.grain_offset);
 
-    header.check_bytes[0] = 0xa;
+   /* header.check_bytes[0] = 0xa;
     header.check_bytes[1] = 0x20;
     header.check_bytes[2] = 0xd;
     header.check_bytes[3] = 0xa;
-
+    */
     /* write all the data */
     ret = qemu_write_full(fd, &magic, sizeof(magic));
     if (ret != sizeof(magic)) {