diff --git a/libisoburn/trunk/xorriso/xorriso.1 b/libisoburn/trunk/xorriso/xorriso.1
index 3614792f..41a3b9bf 100644
--- a/libisoburn/trunk/xorriso/xorriso.1
+++ b/libisoburn/trunk/xorriso/xorriso.1
@@ -2,7 +2,7 @@
 .\" First parameter, NAME, should be all caps
 .\" Second parameter, SECTION, should be 1-8, maybe w/ subsection
 .\" other parameters are allowed: see man(7), man(1)
-.TH XORRISO 1 "Apr 07, 2009"
+.TH XORRISO 1 "Apr 11, 2009"
 .\" Please adjust this date whenever revising the manpage.
 .\"
 .\" Some roff macros, for reference:
@@ -61,6 +61,8 @@ Can restore files from ISO image to disk filesystem (see osirrox).
 .br
 Can record and restore ACL of disk files.
 .br
+Content may get zisofs compressed or filtered by external processes.
+.br
 Can issue commands to mount older sessions on Linux or FreeBSD.
 .br
 Can check media for damages and copy readable blocks to disk.
@@ -1135,7 +1137,8 @@ External filters may also be banned totally at compile time of xorriso.
 By default they are banned if xorriso runs under setuid permission.
 .TP
 \fB\-set_filter\fR name iso_rr_path [***]
-Apply an -external_filter to the given data files in the ISO image.
+Apply an -external_filter or a builtin filter to the given data files in the
+ISO image.
 If the filter suffix is not empty , then it will be applied to the file name.
 Renaming only happens if the filter really gets attached and is not revoked by
 its options.
@@ -1145,8 +1148,8 @@ If the filter has option "remove_suffix", then the filter will only be
 applied if the suffix is present and can be removed.
 Name oversize or collision caused by suffix change will prevent filtering.
 .br
-This command will immediately run the filter once for each file
-in order to determine the output size.
+With most filter types this command will immediately run the filter once for
+each file in order to determine the output size.
 Content reading operations like -extract , -compare and image generation will
 perform further filter runs and deliver filtered content.
 .br
@@ -1158,6 +1161,10 @@ effect (i.e -indev and -outdev are identical).
 The reserved filter name "--remove-all-filters" revokes filtering. This will
 revoke eventual suffix renamings as well. Use "--remove-all-filters+" to
 prevent any suffix renaming.
+.br
+Builtin filters are "--zisofs" and "--zisofs-decode". The former is to be
+applied via -set_filter, the latter is automatically applied if zisofs
+compressed content is detected with a file when loading the ISO image.
 .TP
 \fB\-set_filter_r\fR name isuffix iso_rr_path [***]
 Like -set_filter but affecting all data files below eventual directories.
@@ -1791,6 +1798,18 @@ User id to be used for all files when the new ISO tree gets written to media.
 \fB\-gid\fR gid
 Group id to be used for all files when the new ISO tree gets written to media.
 .TP
+\fB\-zisofs\fR option[:options]
+Set global parameters for zisofs compression. This data format is recognized
+and transparently uncompressed by some Linux kernels. It is to be applied
+via option -set_filter with builtin filter "--zisofs".
+Parameters are:
+.br
+ "level="[0-9] zlib compression: 0=none, 1=fast,..., 9=slow
+.br
+ "block_size="32k|64k|128k size of compression blocks
+.br
+ "default" same as "level=6:block_size=32k"
+.TP
 \fB\-speed\fR number[k|m|c|d|b]
 Set the burn speed. Default is 0 = maximum speed.
 Speed can be given in media dependent numbers or as a
diff --git a/libisoburn/trunk/xorriso/xorriso.c b/libisoburn/trunk/xorriso/xorriso.c
index 9363d194..0a2407ad 100644
--- a/libisoburn/trunk/xorriso/xorriso.c
+++ b/libisoburn/trunk/xorriso/xorriso.c
@@ -4122,6 +4122,8 @@ int Xorriso_new(struct XorrisO ** xorriso,char *progname, int flag)
  m->global_file_mode= 0444;
  m->filters= NULL;
  m->filter_list_closed= 0;
+ m->zlib_level_default= m->zlib_level= 6;
+ m->zisofs_block_size= m->zisofs_block_size_default= (1 << 15);
  m->do_overwrite= 2;
  m->do_reassure= 0;
  m->drive_blacklist= NULL;
@@ -6228,6 +6230,7 @@ int Xorriso_status(struct XorrisO *xorriso, char *filter, FILE *fp, int flag)
  }
 
  Xorriso_status_extf(xorriso, filter, fp, flag & 2);
+ Xorriso_status_zisofs(xorriso, filter, fp, flag & 3);
 
  is_default= !xorriso->allow_graft_points;
  sprintf(line,"-pathspecs %s\n", xorriso->allow_graft_points ? "on" : "off");
@@ -14311,7 +14314,14 @@ int Xorriso_option_help(struct XorrisO *xorriso, int flag)
 "       E.g. by ./configure option --enable-external-filters",
 
 #endif /* ! Xorriso_allow_external_filterS */
-
+"",
+"zisofs is a compression format which is recognized by some Linux kernels.",
+"xorriso supports it by builtin filter \"--zisofs\" which is to be applied by",
+"the user, and by \"--zisofs-decode\" which is applied automatically when",
+"compressed content is detected with a file in the ISO image.",
+"  -zisofs option[:options]",
+"                 Set global zisofs parameters:",
+"                   level=0|...|9 , block_size=32k|64k|128k",
 "",
 "Write-to-media options:",
 "  -rollback      Discard the manipulated ISO image and reload it.",
@@ -17037,6 +17047,75 @@ int Xorriso_option_xattr(struct XorrisO *xorriso, char *mode, int flag)
 }
 
 
+/* Option -zisofs */
+int Xorriso_option_zisofs(struct XorrisO *xorriso, char *mode, int flag)
+{
+ int was_level, was_blocksize, ret, l;
+ double num;
+ char *cpt, *npt, text[16];
+
+ was_level= xorriso->zlib_level;
+ was_blocksize= xorriso->zisofs_block_size;
+ npt= cpt= mode;
+ for(cpt= mode; npt!=NULL; cpt= npt+1) {
+   npt= strchr(cpt,':');
+   if(npt==NULL)
+     l= strlen(cpt);
+   else
+     l= npt-cpt;
+   if(l==0)
+     goto unknown_mode;
+
+   if(strncmp(cpt, "level=", 6) == 0) {
+     sscanf(cpt + 6, "%lf", &num);
+     if(num < 0 || num > 9) {
+       sprintf(xorriso->info_text,
+               "-zisofs: Wrong zlib compression level '%s' (allowed 0...9)",
+               cpt + 6);
+       goto sorry_ex;
+     }
+     xorriso->zlib_level= num;
+
+   } else if(strncmp(cpt, "ziso_used=", 10) == 0 ||
+             strncmp(cpt, "osiz_used=", 10) == 0) {
+     /* (ignored info from -status) */;
+
+   } else if(strncmp(cpt, "block_size=", 11)==0) {
+     num= 0.0;
+     if(l > 11 && l < 27) {
+       strncpy(text, cpt + 11, l - 11);
+       text[l - 11]= 0;
+       num= Scanf_io_size(text, 0);
+     }
+     if (num != (1 << 15) && num != (1 << 16) && num != (1 << 17)) {
+       sprintf(xorriso->info_text,
+               "-zisofs: Unsupported block size (allowed 32k, 64k, 128k)");
+       goto sorry_ex;
+     }
+     xorriso->zisofs_block_size= num;
+
+   } else if(strncmp(cpt, "default", l)==0) {
+     xorriso->zlib_level= xorriso->zlib_level_default;
+     xorriso->zisofs_block_size= xorriso->zisofs_block_size_default;
+
+   } else {
+unknown_mode:;
+     if(l<SfileadrL)
+       sprintf(xorriso->info_text, "-zisofs: unknown mode '%s'", cpt);
+     else
+       sprintf(xorriso->info_text, "-zisofs: oversized mode parameter (%d)",l);
+sorry_ex:
+     Xorriso_msgs_submit(xorriso, 0, xorriso->info_text, 0, "FAILURE", 0);
+     xorriso->zlib_level= was_level;
+     xorriso->zisofs_block_size= was_blocksize;
+     return(0);
+   }
+ }
+ ret= Xorriso_set_zisofs_params(xorriso, 0);
+ return(ret);
+}
+
+
 /* ---------------------------- End Options API ------------------------ */
 
 
@@ -17104,7 +17183,7 @@ int Xorriso_count_args(struct XorrisO *xorriso, int argc, char **argv,
     "reassure","report_about","rom_toc_scan",
     "session_log","speed","split_size","status","status_history_max",
     "stream_recording","temp_mem_limit",
-    "uid","unregister_filter","use_readline","volid","xattr",
+    "uid","unregister_filter","use_readline","volid","xattr","zisofs",
     ""
  };
  static char arg2_commands[][40]= {
@@ -17882,6 +17961,10 @@ next_command:;
    (*idx)++;
    ret= Xorriso_option_xattr(xorriso, arg1, 0);
 
+ } else if(strcmp(cmd,"zisofs")==0) {
+   (*idx)++;
+   ret= Xorriso_option_zisofs(xorriso, arg1, 0);
+
  } else if(strcmp(cmd, xorriso->list_delimiter)==0){
    /* tis ok */;
 
diff --git a/libisoburn/trunk/xorriso/xorriso.h b/libisoburn/trunk/xorriso/xorriso.h
index 953299df..b103a752 100644
--- a/libisoburn/trunk/xorriso/xorriso.h
+++ b/libisoburn/trunk/xorriso/xorriso.h
@@ -761,6 +761,10 @@ int Xorriso_option_volid(struct XorrisO *xorriso, char *volid, int flag);
 /* Option -xattr "on"|"off" */
 int Xorriso_option_xattr(struct XorrisO *xorriso, char *mode, int flag);
 
+/* Option -zisofs */
+int Xorriso_option_zisofs(struct XorrisO *xorriso, char *mode, int flag);
+
+
 #endif /* Xorriso_includeD */
 
 
diff --git a/libisoburn/trunk/xorriso/xorriso_private.h b/libisoburn/trunk/xorriso/xorriso_private.h
index 705089e6..edcd4978 100644
--- a/libisoburn/trunk/xorriso/xorriso_private.h
+++ b/libisoburn/trunk/xorriso/xorriso_private.h
@@ -130,6 +130,11 @@ struct XorrisO { /* the global context of xorriso */
  struct Xorriso_lsT *filters;
  int filter_list_closed;
 
+ int zlib_level;
+ int zlib_level_default;
+ int zisofs_block_size;
+ int zisofs_block_size_default;
+
  int do_overwrite; /* 0=off, 1=on, 2=nondir */
  int do_reassure;  /* 0=off, 1=on, 2=tree */
 
diff --git a/libisoburn/trunk/xorriso/xorriso_timestamp.h b/libisoburn/trunk/xorriso/xorriso_timestamp.h
index 048fd38f..f987b9f9 100644
--- a/libisoburn/trunk/xorriso/xorriso_timestamp.h
+++ b/libisoburn/trunk/xorriso/xorriso_timestamp.h
@@ -1 +1 @@
-#define Xorriso_timestamP "2009.04.11.125331"
+#define Xorriso_timestamP "2009.04.11.172644"
diff --git a/libisoburn/trunk/xorriso/xorrisoburn.c b/libisoburn/trunk/xorriso/xorrisoburn.c
index 4b0f9e34..25d43204 100644
--- a/libisoburn/trunk/xorriso/xorrisoburn.c
+++ b/libisoburn/trunk/xorriso/xorrisoburn.c
@@ -135,6 +135,7 @@ int Xorriso_startup_libraries(struct XorrisO *xorriso, int flag)
  int ret, major, minor, micro;
  char *handler_prefix= NULL;
  char *queue_sev, *print_sev, reason[1024];
+ struct iso_zisofs_ctrl zisofs_ctrl= {0, 6, 15};
 
 
 /* First an ugly compile time check for header version compatibility.
@@ -230,6 +231,14 @@ LIBISOBURN_MISCONFIGURATION_ = 0;
 
  sprintf(handler_prefix, "%s : ", xorriso->progname);
  burn_set_signal_handling(handler_prefix, NULL, 0);
+
+ ret = iso_zisofs_get_params(&zisofs_ctrl, 0);
+ if (ret == 1) {
+   xorriso->zisofs_block_size= xorriso->zisofs_block_size_default=
+       (1 << zisofs_ctrl.block_size_log2);
+   xorriso->zlib_level= xorriso->zlib_level_default=
+       zisofs_ctrl.compression_level;
+ }
  
  Xorriso_process_msg_queues(xorriso,0);
  if(reason[0]) {
@@ -10022,6 +10031,7 @@ int Xorriso_set_filter(struct XorrisO *xorriso, void *in_node,
  xorriso->volset_change_pending= 1;
  */
  ret= filter_ret;
+
 ex:;
  if(old_name != NULL)
    free(old_name);
@@ -10326,3 +10336,49 @@ ex:;
  return(ret); 
 }
 
+
+int Xorriso_set_zisofs_params(struct XorrisO *xorriso, int flag)
+{
+ int ret;
+ struct iso_zisofs_ctrl ctrl;
+
+ ctrl.version= 0;
+ ctrl.compression_level= xorriso->zlib_level;
+ if(xorriso->zisofs_block_size == (1 << 16))
+   ctrl.block_size_log2= 16;
+ else if(xorriso->zisofs_block_size == (1 << 17))
+   ctrl.block_size_log2= 17;
+ else
+   ctrl.block_size_log2= 15;
+ ret= iso_zisofs_set_params(&ctrl, 0);
+ Xorriso_process_msg_queues(xorriso,0);
+ if(ret < 0) {
+   Xorriso_report_iso_error(xorriso, "", ret,
+                      "Error when setting zisofs parameters", 0, "FAILURE", 1);
+   return(0);
+ }
+ return(1);
+}
+
+
+int Xorriso_status_zisofs(struct XorrisO *xorriso, char *filter, FILE *fp,
+                          int flag)
+/*
+ bit1= do only report to fp
+*/ 
+{
+ off_t ziso_count= 0, osiz_count= 0;
+
+ iso_zisofs_get_refcounts(&ziso_count, &osiz_count, 0);
+ if((flag & 1) && xorriso->zlib_level == xorriso->zlib_level_default &&
+    xorriso->zisofs_block_size == xorriso->zisofs_block_size_default &&
+    ziso_count == 0 && osiz_count == 0)
+   return 2;
+ sprintf(xorriso->result_line,
+         "-zisofs level=%d:block_size=%dk:ziso_used=%.f:osiz_used=%.f\n",
+         xorriso->zlib_level, xorriso->zisofs_block_size / 1024,
+         (double) ziso_count, (double) osiz_count);
+ Xorriso_status_result(xorriso, filter, fp, flag&2);
+ return(1);
+}
+
diff --git a/libisoburn/trunk/xorriso/xorrisoburn.h b/libisoburn/trunk/xorriso/xorrisoburn.h
index 0b9b4495..78f36931 100644
--- a/libisoburn/trunk/xorriso/xorrisoburn.h
+++ b/libisoburn/trunk/xorriso/xorrisoburn.h
@@ -448,6 +448,11 @@ int Xorriso_destroy_all_extf(struct XorrisO *xorriso, int flag);
 int Xorriso_show_stream(struct XorrisO *xorriso, void *in_node,
                         char *path, int flag);
 
+int Xorriso_set_zisofs_params(struct XorrisO *xorriso, int flag);
+
+int Xorriso_status_zisofs(struct XorrisO *xorriso, char *filter, FILE *fp,
+                          int flag);
+
 
 /* A pseudo file type for El-Torito bootsectors as in man 2 stat :
    For now take the highest possible value.