--- squashfs-tools/lzma_xz_wrapper.c
+++ squashfs-tools/lzma_xz_wrapper.c
@@ -35,6 +35,8 @@
 #define LZMA_OPTIONS 5
 #define MEMLIMIT (32 * 1024 * 1024)
 
+extern unsigned short squashfs_major_version;
+
 static int lzma_compress(void *dummy, void *dest, void *src,  int size,
 	int block_size, int *error)
 {
@@ -102,6 +104,7 @@
 	lzma_stream strm = LZMA_STREAM_INIT;
 	int uncompressed_size = 0, res;
 	unsigned char lzma_header[LZMA_HEADER_SIZE];
+	int lzmaHeaderLess = (squashfs_major_version < 4);
 
 	res = lzma_alone_decoder(&strm, MEMLIMIT);
 	if(res != LZMA_OK) {
@@ -109,6 +112,20 @@
 		goto failed;
 	}
 
+if (lzmaHeaderLess) {
+	#define _DICT_SIZE (1 << (9 + 14))
+	#define _LC        3
+	#define _LP        0
+	#define _PB        2
+	int i;
+	unsigned int dictSize = _DICT_SIZE;
+	lzma_header[0] = (unsigned char)((_PB * 5 + _LP) * 9 + _LC);
+	for (i = 1; i<LZMA_PROPS_SIZE; i++) {
+		lzma_header[i] = (unsigned char)(dictSize >> (8 * (i-1)));
+	}
+
+	uncompressed_size = outsize;
+} else {
 	memcpy(lzma_header, src, LZMA_HEADER_SIZE);
 	uncompressed_size = lzma_header[LZMA_PROPS_SIZE] |
 		(lzma_header[LZMA_PROPS_SIZE + 1] << 8) |
@@ -119,6 +136,7 @@
 		res = 0;
 		goto failed;
 	}
+}
 
 	memset(lzma_header + LZMA_PROPS_SIZE, 255, LZMA_UNCOMP_SIZE);
 
@@ -134,8 +152,8 @@
 		goto failed;
 	}
 
-	strm.next_in = src + LZMA_HEADER_SIZE;
-	strm.avail_in = size - LZMA_HEADER_SIZE;
+	strm.next_in  = src  + (lzmaHeaderLess ? 0 : LZMA_HEADER_SIZE);
+	strm.avail_in = size - (lzmaHeaderLess ? 0 : LZMA_HEADER_SIZE);
 
 	res = lzma_code(&strm, LZMA_FINISH);
 	lzma_end(&strm);
--- squashfs-tools/mksquashfs.c
+++ squashfs-tools/mksquashfs.c
@@ -89,6 +89,7 @@
 #endif
 
 int fd;
+unsigned short squashfs_major_version = SQUASHFS_MAJOR;
 struct squashfs_super_block sBlk;
 
 /* filesystem flags for building */
--- squashfs-tools/unsquashfs.c
+++ squashfs-tools/unsquashfs.c
@@ -47,6 +47,7 @@
 /* user options that control parallelisation */
 int processors = -1;
 
+unsigned short squashfs_major_version = SQUASHFS_MAJOR;
 struct super_block sBlk;
 squashfs_operations s_ops;
 struct compressor *comp;
@@ -1640,9 +1641,8 @@
 		sBlk.s.bytes_used / 1024.0, sBlk.s.bytes_used /
 		(1024.0 * 1024.0));
 
+	printf("Compression %s\n", comp->name);
 	if(sBlk.s.s_major == 4) {
-		printf("Compression %s\n", comp->name);
-
 		if(SQUASHFS_COMP_OPTS(sBlk.s.flags)) {
 			char buffer[SQUASHFS_METADATA_SIZE] __attribute__ ((aligned));
 			int bytes;
@@ -1845,7 +1845,7 @@
 	sBlk.s.fragments = sBlk_3.fragments;
 	sBlk.s.block_log = sBlk_3.block_log;
 	sBlk.s.flags = sBlk_3.flags;
-	sBlk.s.s_major = sBlk_3.s_major;
+	sBlk.s.s_major = squashfs_major_version = sBlk_3.s_major;
 	sBlk.s.s_minor = sBlk_3.s_minor;
 	sBlk.s.root_inode = sBlk_3.root_inode;
 	sBlk.s.bytes_used = sBlk_3.bytes_used;
@@ -1900,9 +1900,9 @@
 	}
 
 	/*
-	 * 1.x, 2.x and 3.x filesystems use gzip compression.
+	 * 1.x, 2.x and 3.x filesystems use gzip or lzma1 (superblock.minor==76) compression.
 	 */
-	comp = lookup_compressor("gzip");
+	comp = lookup_compressor((sBlk.s.s_minor == 76) ? "lzma" : "gzip");
 	return TRUE;
 
 failed_mount:
@@ -2706,6 +2706,8 @@
 		exit(0);
 	}
 
+	printf("Filesystem on %s is %s compressed (%d:%d)\n", argv[i], comp->name, sBlk.s.s_major, sBlk.s.s_minor);
+
 	if(!check_compression(comp))
 		exit(1);