Index: apps/tagcache.c
===================================================================
--- apps/tagcache.c	(revision 13614)
+++ apps/tagcache.c	(working copy)
@@ -108,11 +108,13 @@
 
 /* Tags we want to get sorted (loaded to the tempbuf). */
 static const int sorted_tags[] = { tag_artist, tag_album, tag_genre, 
-    tag_composer, tag_comment, tag_albumartist, tag_title };
+    tag_composer, tag_comment, tag_albumartist, tag_title, tag_sortartist,
+    tag_sortalbum, tag_sorttitle };
 
 /* Uniqued tags (we can use these tags with filters and conditional clauses). */
 static const int unique_tags[] = { tag_artist, tag_album, tag_genre, 
-    tag_composer, tag_comment, tag_albumartist };
+    tag_composer, tag_comment, tag_albumartist, tag_sortartist, tag_sortalbum,
+    tag_sorttitle };
 
 /* Numeric tags (we can use these tags with conditional clauses). */
 static const int numeric_tags[] = { tag_year, tag_tracknumber, tag_length, 
@@ -124,7 +126,8 @@
 /* String presentation of the tags defined in tagcache.h. Must be in correct order! */
 static const char *tags_str[] = { "artist", "album", "genre", "title", 
     "filename", "composer", "comment", "albumartist", "year", "tracknumber", 
-    "bitrate", "length", "playcount", "rating", "playtime", "lastplayed", "commitid" };
+    "bitrate", "length", "playcount", "rating", "playtime", "lastplayed", "commitid",
+    "sortartist", "sortalbum", "sorttitle" };
 
 /* Status information of the tagcache. */
 static struct tagcache_stat tc_stat;
@@ -170,7 +173,7 @@
 
 /* For the endianess correction */
 static const char *tagfile_entry_ec   = "ss";
-static const char *index_entry_ec     = "llllllllllllllllll"; /* (1 + TAG_COUNT) * l */
+static const char *index_entry_ec     = "lllllllllllllllllllll"; /* (1 + TAG_COUNT) * l */
 static const char *tagcache_header_ec = "lll";
 static const char *master_header_ec   = "llllll";
 
@@ -1531,6 +1534,9 @@
     id3->composer     = get_tag_string(entry, tag_composer);
     id3->comment      = get_tag_string(entry, tag_comment);
     id3->albumartist  = get_tag_string(entry, tag_albumartist);
+    id3->sort_title   = get_tag_string(entry, tag_sorttitle);
+    id3->sort_artist  = get_tag_string(entry, tag_sortartist);
+    id3->sort_album   = get_tag_string(entry, tag_sortalbum);
 
     id3->playcount  = get_tag_numeric(entry, tag_playcount);
     id3->rating     = get_tag_numeric(entry, tag_rating);
@@ -1693,6 +1699,9 @@
     ADD_TAG(entry, tag_composer, &track.id3.composer);
     ADD_TAG(entry, tag_comment, &track.id3.comment);
     ADD_TAG(entry, tag_albumartist, &track.id3.albumartist);
+    ADD_TAG(entry, tag_sorttitle, &track.id3.sort_title);
+    ADD_TAG(entry, tag_sortartist, &track.id3.sort_artist);
+    ADD_TAG(entry, tag_sortalbum, &track.id3.sort_album);
     entry.data_length = offset;
     
     /* Write the header */
@@ -1706,7 +1715,9 @@
     write_item(track.id3.genre_string);
     write_item(track.id3.composer);
     write_item(track.id3.comment);
-    write_item(track.id3.albumartist);
+    write_item(track.id3.sort_title);
+    write_item(track.id3.sort_artist);
+    write_item(track.id3.sort_album);
     total_entry_count++;    
 }
 
Index: apps/tagcache.h
===================================================================
--- apps/tagcache.h	(revision 13614)
+++ apps/tagcache.h	(working copy)
@@ -25,13 +25,14 @@
 enum tag_type { tag_artist = 0, tag_album, tag_genre, tag_title,
     tag_filename, tag_composer, tag_comment, tag_albumartist, tag_year, 
     tag_tracknumber, tag_bitrate, tag_length, tag_playcount, tag_rating, 
-    tag_playtime, tag_lastplayed, tag_commitid,
+    tag_playtime, tag_lastplayed, tag_commitid, tag_sortartist,
+    tag_sortalbum, tag_sorttitle,
     /* Virtual tags */
     tag_virt_length_min, tag_virt_length_sec,
     tag_virt_playtime_min, tag_virt_playtime_sec,
     tag_virt_entryage, tag_virt_autoscore };
 
-#define TAG_COUNT 17
+#define TAG_COUNT 20
 
 /* Maximum length of a single tag. */
 #define TAG_MAXLEN (MAX_PATH*2)
Index: firmware/export/id3.h
===================================================================
--- firmware/export/id3.h	(revision 13614)
+++ firmware/export/id3.h	(working copy)
@@ -149,6 +149,11 @@
     char* composer;
     char* comment;
     char* albumartist;
+#ifdef HAVE_TAGCACHE
+    char* sort_title;
+    char* sort_album;
+    char* sort_artist;
+#endif
     int tracknum;
     int version;
     int layer;
Index: firmware/id3.c
===================================================================
--- firmware/id3.c	(revision 13614)
+++ firmware/id3.c	(working copy)
@@ -453,6 +453,11 @@
     { "COMM", 4, offsetof(struct mp3entry, comment), NULL, false }, 
     { "TCON", 4, offsetof(struct mp3entry, genre_string), &parsegenre, false },
     { "TCO",  3, offsetof(struct mp3entry, genre_string), &parsegenre, false },
+#ifdef HAVE_TAGCACHE
+    { "TSOA", 4, offsetof(struct mp3entry, sort_album), NULL, false },
+    { "TSOP", 4, offsetof(struct mp3entry, sort_artist), NULL, false },
+    { "TSOT", 4, offsetof(struct mp3entry, sort_title), NULL, false },
+#endif
 #if CONFIG_CODEC == SWCODEC
     { "TXXX", 4, 0, &parseuser, false },
     { "RVA2", 4, 0, &parserva2, true },