diff --git a/cdrskin/cdrskin_timestamp.h b/cdrskin/cdrskin_timestamp.h
index 596ff86..986dfdc 100644
--- a/cdrskin/cdrskin_timestamp.h
+++ b/cdrskin/cdrskin_timestamp.h
@@ -1 +1 @@
-#define Cdrskin_timestamP "2006.10.09.083438"
+#define Cdrskin_timestamP "2006.10.09.123518"
diff --git a/libburn/asserts.txt b/libburn/asserts.txt
index 2c4ca2f..504fa96 100644
--- a/libburn/asserts.txt
+++ b/libburn/asserts.txt
@@ -229,60 +229,107 @@ ts A61007
 
 ------------------------------------------------------------------------------
 
-   17) libburn/mmc.c:	assert(o->drive == d);
+++ 17) libburn/mmc.c:	assert(o->drive == d);
 mmc_close_disc():
 alias: struct burn_drive.close_disc()
 Parameters struct burn_drive and struct burn_write_opts do not match
 
 Called by -nobody- ?
 
-=> Disable unused function ?
+( => Disable unused function ? )
+=> removed redundant parameter struct burn_drive
+
+ts A61009
 
 ------------------------------------------------------------------------------
 
-   18) libburn/mmc.c:	assert(o->drive == d);
+++ 18) libburn/mmc.c:	assert(o->drive == d);
 mmc_close_session():
 Same as 17)
 alias: struct burn_drive.close_session()
 
 Called by -nobody- ?
 
-=> Disable unused function ?
+( => Disable unused function ? )
+=> removed redundant parameter struct burn_drive
+
+ts A61009
 
 ------------------------------------------------------------------------------
 
-   19) libburn/mmc.c:	assert(buf->bytes >= buf->sectors);	/* can be == at 0... */
+++ 19) libburn/mmc.c:	assert(buf->bytes >= buf->sectors);	/* can be == at 0... */
 mmc_write_12():
 - Unclear what .bytes and .sectors mean in struct buffer -
 
 Called by -nobody- ?
 
-=> Disable unused function ?
+=> problems with filling the write buffer have to be handled by callers
+=> delete assert 
+
+ts A61009
 
 ------------------------------------------------------------------------------
 
-   20) libburn/mmc.c:	assert(buf->bytes >= buf->sectors);	/* can be == at 0... */
+++ 20) libburn/mmc.c:	assert(buf->bytes >= buf->sectors);	/* can be == at 0... */
 mmc_write():
 - Unclear what .bytes and .sectors mean in struct buffer -
-alias: struct burn_drive.write()
 
+libburn/mmc.c:          c.page->sectors = errorblock - start + 1;
+mmc_read_sectors() by toc_find_modes() by mmc_read_toc() alias drive.read_toc()
+by burn_drive_grab()
+This seems to be unrelated to mmc_write().
+
+libburn/sector.c:       out->sectors++;
+get_sector()
+Seems to hand out sector start pointer in opts->drive->buffer
+and to count reservation transactions as well as reserved bytes.
+Ensures out->bytes >= out->sectors
+
+
+libburn/mmc.c:  c.page->bytes = s->count * 8;
+mmc_send_cue_sheet()
+Does not use mmc_write() but directly (sg_)issue_command()
+
+libburn/sector.c:       out->bytes += seclen;
+get_sector()
+See above
+Ensures out->bytes >= out->sectors
+
+libburn/spc.c:  c.page->bytes = 8 + 2 + d->mdata->retry_page_length;
+spc_select_error_params()
+Does not use mmc_write() but directly (sg_)issue_command()
+
+libburn/spc.c:  c.page->bytes = 8 + 2 + d->mdata->write_page_length;
+spc_select_error_params()
+Does not use mmc_write() but directly (sg_)issue_command()
+
+libburn/spc.c:          c.page->bytes = 8 + 2 + 0x32;
+spc_probe_write_modes()
+Does not use mmc_write() but directly (sg_)issue_command()
+
+alias struct burn_drive.write()
 Called by static get_sector, by many
 Called by burn_write_flush
 Called by burn_write_track
 
-=> ???
+=> problems with filling the write buffer have to be handled by callers
+=> delete assert 
+
+ts A61009
 
 ------------------------------------------------------------------------------
 
-   21) libburn/mmc.c:	assert(((dlen - 2) % 11) == 0);
+++ 21) libburn/mmc.c:	assert(((dlen - 2) % 11) == 0);
 mmc_read_toc():
 - Is defunct -
 
 => :)
 
+ts A61009
+
 ------------------------------------------------------------------------------
 
-   22) libburn/mmc.c:	assert(len >= 0);
+++ 22) libburn/mmc.c:	assert(len >= 0);
 mmc_read_sectors():
 Catches a bad parameter
 
@@ -294,9 +341,11 @@ Called by toc_find_modes(), problem cannot occur: mem.sectors = 1;
 (=> in burn_disc_read() check page.sectors before d->read_sectors() )
 => :)
 
+ts A61009
+
 ------------------------------------------------------------------------------
 
-   23) libburn/mmc.c:	assert(d->busy);
+++ 23) libburn/mmc.c:	assert(d->busy);
 mmc_read_sectors():
 Catches use of a drive that is not marked as busy
 
@@ -307,6 +356,8 @@ Called by toc_find_modes(), does the same assert. To be solved there.
 : Severe Libburn Error
 => :)
 
+ts A61009
+
 ------------------------------------------------------------------------------
 
 ++ 24) libburn/options.c:	assert(0);
@@ -563,7 +614,7 @@ ts A61008
 
 ------------------------------------------------------------------------------
 
-   43) libburn/structure.c:	assert(s->track != NULL);
+++ 43) libburn/structure.c:	assert(s->track != NULL);
 API burn_session_remove_track()
 An application supplied pointer is NULL
 
diff --git a/libburn/mmc.c b/libburn/mmc.c
index 17705e2..b4a6ade 100644
--- a/libburn/mmc.c
+++ b/libburn/mmc.c
@@ -1,6 +1,8 @@
 /* -*- indent-tabs-mode: t; tab-width: 8; c-basic-offset: 8; -*- */
 
-#include <assert.h>
+/* ts A61009 */
+/* #include <a ssert.h> */
+
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
@@ -18,6 +20,12 @@
 #include "structure.h"
 #include "options.h"
 
+/* ts A61005 */
+#include "libdax_msgs.h"
+extern struct libdax_msgs *libdax_messenger;
+
+
+
 static unsigned char MMC_GET_TOC[] = { 0x43, 2, 2, 0, 0, 0, 0, 16, 0, 0 };
 static unsigned char MMC_GET_ATIP[] = { 0x43, 2, 4, 0, 0, 0, 0, 16, 0, 0 };
 static unsigned char MMC_GET_DISC_INFO[] =
@@ -99,19 +107,43 @@ int mmc_get_nwa(struct burn_drive *d)
 		+ (data[14] << 8) + data[15];
 }
 
-void mmc_close_disc(struct burn_drive *d, struct burn_write_opts *o)
+/* ts A61009 : function is obviously unused. */
+/* void mmc_close_disc(struct burn_drive *d, struct burn_write_opts *o) */
+void mmc_close_disc(struct burn_write_opts *o)
 {
+	struct burn_drive *d;
+
 	mmc_function_spy("mmc_close_disc");
-	assert(o->drive == d);
+
+	libdax_msgs_submit(libdax_messenger, -1, 0x00000002,
+			   LIBDAX_MSGS_SEV_DEBUG, LIBDAX_MSGS_PRIO_ZERO,
+			   "HOW THAT ? mmc_close_disc() was called", 0, 0);
+
+	/* ts A61009 : made impossible by removing redundant parameter d */
+	/* a ssert(o->drive == d); */
+	d = o->drive;
+
 	o->multi = 0;
 	spc_select_write_params(d, o);
 	mmc_close(d, 1, 0);
 }
 
-void mmc_close_session(struct burn_drive *d, struct burn_write_opts *o)
+/* ts A61009 : function is obviously unused. */
+/* void mmc_close_session(struct burn_drive *d, struct burn_write_opts *o) */
+void mmc_close_session(struct burn_write_opts *o)
 {
+	struct burn_drive *d;
+
 	mmc_function_spy("mmc_close_session");
-	assert(o->drive == d);
+
+	libdax_msgs_submit(libdax_messenger, -1, 0x00000002,
+			   LIBDAX_MSGS_SEV_DEBUG, LIBDAX_MSGS_PRIO_ZERO,
+			   "HOW THAT ? mmc_close_session() was called", 0, 0);
+
+	/* ts A61009 : made impossible by removing redundant parameter d */
+	/* a ssert(o->drive == d); */
+	d = o->drive;
+
 	o->multi = 3;
 	spc_select_write_params(d, o);
 	mmc_close(d, 1, 0);
@@ -121,7 +153,12 @@ void mmc_close(struct burn_drive *d, int session, int track)
 {
 	struct command c;
 
-	mmc_function_spy("mmc_close_session");
+	mmc_function_spy("mmc_close");
+
+	libdax_msgs_submit(libdax_messenger, -1, 0x00000002,
+			   LIBDAX_MSGS_SEV_DEBUG, LIBDAX_MSGS_PRIO_ZERO,
+			   "HOW THAT ? mmc_close() was called", 0, 0);
+
 	c.retry = 1;
 	c.oplen = sizeof(MMC_CLOSE);
 	memcpy(c.opcode, MMC_CLOSE, sizeof(MMC_CLOSE));
@@ -154,6 +191,7 @@ void mmc_get_event(struct burn_drive *d)
 		   c.page->data[5], c.page->data[6], c.page->data[7]);
 }
 
+
 void mmc_write_12(struct burn_drive *d, int start, struct buffer *buf)
 {
 	struct command c;
@@ -161,7 +199,10 @@ void mmc_write_12(struct burn_drive *d, int start, struct buffer *buf)
 
 	mmc_function_spy("mmc_write_12");
 	len = buf->sectors;
-	assert(buf->bytes >= buf->sectors);	/* can be == at 0... */
+
+	/* ts A61009 */
+	/* a ssert(buf->bytes >= buf->sectors);*/	/* can be == at 0... */
+
 	burn_print(100, "trying to write %d at %d\n", len, start);
 	memcpy(c.opcode, MMC_WRITE_12, sizeof(MMC_WRITE_12));
 	c.retry = 1;
@@ -195,7 +236,10 @@ int mmc_write(struct burn_drive *d, int start, struct buffer *buf)
 		return BE_CANCELLED;
 
 	len = buf->sectors;
-	assert(buf->bytes >= buf->sectors);	/* can be == at 0... */
+
+	/* ts A61009 : buffer fill problems are to be handled by caller */
+	/* a ssert(buf->bytes >= buf->sectors);*/	/* can be == at 0... */
+
 	burn_print(100, "trying to write %d at %d\n", len, start);
 	memcpy(c.opcode, MMC_WRITE_10, sizeof(MMC_WRITE_10));
 	c.retry = 1;
@@ -251,7 +295,8 @@ void mmc_read_toc(struct burn_drive *d)
 /*
 	some drives fail this check.
 
-	assert(((dlen - 2) % 11) == 0);
+	ts A61007 : if re-enabled then not via Assert.
+	a ssert(((dlen - 2) % 11) == 0);
 */
 	d->toc_entry = malloc(d->toc_entries * sizeof(struct burn_toc_entry));
 	tdata = c.page->data + 4;
@@ -382,9 +427,14 @@ void mmc_read_sectors(struct burn_drive *d,
 	struct command c;
 
 	mmc_function_spy("mmc_read_sectors");
-	assert(len >= 0);
-/* if the drive isn't busy, why the hell are we here? */
-	assert(d->busy);
+
+	/* ts A61009 : to be ensured by callers */
+	/* a ssert(len >= 0); */
+
+/* if the drive isn't busy, why the hell are we here? */ 
+	/* ts A61006 : i second that question */
+	/* a ssert(d->busy); */
+
 	burn_print(12, "reading %d from %d\n", len, start);
 	memcpy(c.opcode, MMC_READ_CD, sizeof(MMC_READ_CD));
 	c.retry = 1;
diff --git a/libburn/mmc.h b/libburn/mmc.h
index 95275b7..6a0044e 100644
--- a/libburn/mmc.h
+++ b/libburn/mmc.h
@@ -12,8 +12,13 @@ struct cue_sheet;
 /* MMC commands */
 
 void mmc_read(struct burn_drive *);
-void mmc_close_session(struct burn_drive *, struct burn_write_opts *);
-void mmc_close_disc(struct burn_drive *, struct burn_write_opts *);
+
+/* ts A61009 : removed redundant parameter d in favor of o->drive */
+/* void mmc_close_session(struct burn_drive *, struct burn_write_opts *); */
+/* void mmc_close_disc(struct burn_drive *, struct burn_write_opts *); */
+void mmc_close_session(struct burn_write_opts *o);
+void mmc_close_disc(struct burn_write_opts *o);
+
 void mmc_close(struct burn_drive *, int session, int track);
 void mmc_get_event(struct burn_drive *);
 int mmc_write(struct burn_drive *, int start, struct buffer *buf);
diff --git a/libburn/read.c b/libburn/read.c
index e404ec2..4f27207 100644
--- a/libburn/read.c
+++ b/libburn/read.c
@@ -47,6 +47,9 @@ void burn_disc_read(struct burn_drive *d, const struct burn_read_opts *o)
 	a ssert(d->toc->valid);
 	a ssert(o->datafd != -1);
 
+	/* moved up from spc_select_error_params alias d->send_parameters() */
+	a ssert(d->mdata->valid);
+
 /* XXX not sure this is a good idea.  copy it? */
 /* XXX also, we have duplicated data now, do we remove the fds from struct 
 drive, or only store a subset of the _opts structs in drives */
@@ -56,6 +59,7 @@ drive, or only store a subset of the _opts structs in drives */
 	d->set_speed(d, speed, 0);
 
 	d->params.retries = o->hardware_error_retries;
+
 	d->send_parameters(d, o);
 
 	d->cancel = 0;
@@ -133,7 +137,10 @@ drive, or only store a subset of the _opts structs in drives */
 		page.sectors = (finish < maxsects) ? finish : maxsects;
 		printf("reading %d sectors from %d\n", page.sectors,
 		       drive_lba);
-		d->read_sectors(d, drive_lba, page.sectors, o, &page);
+
+		/* >>> ts A61009 : ensure page.sectors >= 0 before calling */
+		d->r ead_sectors(d, drive_lba, page.sectors, o, &page);
+
 		printf("Read %d\n", page.sectors);
 	}
 #endif
diff --git a/libburn/sector.c b/libburn/sector.c
index a1ec9f1..3b1319e 100644
--- a/libburn/sector.c
+++ b/libburn/sector.c
@@ -148,6 +148,9 @@ static void get_bytes(struct burn_track *track, int count, unsigned char *data)
 		return;
 	memset(data + curr, 0, shortage);
 }
+
+/* ts A61009 : seems to hand out sector start pointer in opts->drive->buffer
+		and to count hand outs as well as reserved bytes */
 static unsigned char *get_sector(struct burn_write_opts *opts, int inmode)
 {
 	struct burn_drive *d = opts->drive;
@@ -160,7 +163,13 @@ static unsigned char *get_sector(struct burn_write_opts *opts, int inmode)
 	if (outmode == 0)
 		outmode = inmode;
 
-	seclen = burn_sector_length(outmode) + burn_subcode_length(outmode);
+	/* ts A61009 : react on eventual failure of burn_sector_length()
+			(should not happen if API tested properly).
+			Ensures out->bytes >= out->sectors  */
+	seclen = burn_sector_length(outmode);
+	if (seclen <= 0)
+		return NULL;
+	seclen += burn_subcode_length(outmode);
 
 	if (out->bytes + (seclen) >= BUFFER_SIZE) {
 		int err;
diff --git a/libburn/transport.h b/libburn/transport.h
index 47ae092..7b90317 100644
--- a/libburn/transport.h
+++ b/libburn/transport.h
@@ -161,9 +161,16 @@ struct burn_drive
 	void (*sync_cache) (struct burn_drive *);
 	int (*get_erase_progress) (struct burn_drive *);
 	int (*get_nwa) (struct burn_drive *);
-	void (*close_disc) (struct burn_drive * d, struct burn_write_opts * o);
-	void (*close_session) (struct burn_drive * d,
+
+	/* ts A61009 : removed d in favor of o->drive */
+	/* void (*close_disc) (struct burn_drive * d,
+				 struct burn_write_opts * o);
+	   void (*close_session) (struct burn_drive * d,
 			       struct burn_write_opts * o);
+	*/
+	void (*close_disc) (struct burn_write_opts * o);
+	void (*close_session) ( struct burn_write_opts * o);
+
 	int (*test_unit_ready) (struct burn_drive * d);
 	void (*probe_write_modes) (struct burn_drive * d);
 	struct params params;