diff --git a/src/mu-maildir.c b/src/mu-maildir.c
index c57535cc..eae032fd 100644
--- a/src/mu-maildir.c
+++ b/src/mu-maildir.c
@@ -830,7 +830,7 @@ char*
 mu_maildir_get_path_from_flags (const char *oldpath, MuMsgFlags newflags)
 {
 	char *newname, *newdir, *newpath;
-		
+	
 	g_return_val_if_fail (oldpath, NULL);
 	g_return_val_if_fail (newflags != MU_MSG_FLAG_NONE, NULL);
 	/* if MU_MSG_FLAG_NEW is set, it must be the only flag */
diff --git a/src/mu-msg-flags.c b/src/mu-msg-flags.c
index 18a4eb3a..3599a7e6 100644
--- a/src/mu-msg-flags.c
+++ b/src/mu-msg-flags.c
@@ -26,39 +26,38 @@
 #include "mu-msg-flags.h"
 
 
-/* put these in alpha-order, so output strings are ordered thusly
- * note, these should be in lower-case, otherwise Xapian gets
- * confused...
+/* put these in alpha-order, so output strings are ordered correctly
+ * (that's the way the Maildir spec teaches us)
  */
 static const MuMsgFlags ALL_FLAGS[] = {
-	/* a */ MU_MSG_FLAG_HAS_ATTACH,	
-	/* d */ MU_MSG_FLAG_DRAFT,
-	/* f */ MU_MSG_FLAG_FLAGGED,
-	/* n */ MU_MSG_FLAG_NEW,
-	/* p */ MU_MSG_FLAG_PASSED,
-	/* r */ MU_MSG_FLAG_REPLIED,
-	/* s */ MU_MSG_FLAG_SEEN,
-	/* t */ MU_MSG_FLAG_TRASHED,
-	/* u */ MU_MSG_FLAG_UNREAD,
-	/* x */ MU_MSG_FLAG_ENCRYPTED,
-	/* z */ MU_MSG_FLAG_SIGNED
+	/* a */ MU_MSG_FLAG_HAS_ATTACH, /* non-maildir flag */
+	/* D */ MU_MSG_FLAG_DRAFT,
+	/* F */ MU_MSG_FLAG_FLAGGED,
+	/* N */ MU_MSG_FLAG_NEW,         
+	/* P */ MU_MSG_FLAG_PASSED,
+	/* R */ MU_MSG_FLAG_REPLIED,
+	/* S */ MU_MSG_FLAG_SEEN,
+	/* T */ MU_MSG_FLAG_TRASHED,
+	/* U */ MU_MSG_FLAG_UNREAD,    /* pseudo flag */
+	/* x */ MU_MSG_FLAG_ENCRYPTED, /* non-maildir flag */
+	/* z */ MU_MSG_FLAG_SIGNED     /* non-maildir flag */
 };
 
 
 MuMsgFlags
 mu_msg_flag_from_char (char k)
 {
-	switch (g_ascii_tolower(k)) {
-	case 'n': return MU_MSG_FLAG_NEW;		
-	case 'p': return MU_MSG_FLAG_PASSED;
-	case 'r': return MU_MSG_FLAG_REPLIED;
-	case 's': return MU_MSG_FLAG_SEEN;
-	case 't': return MU_MSG_FLAG_TRASHED;
-	case 'd': return MU_MSG_FLAG_DRAFT;
-	case 'f': return MU_MSG_FLAG_FLAGGED;
+	switch (k) {
+	case 'N': return MU_MSG_FLAG_NEW;		
+	case 'P': return MU_MSG_FLAG_PASSED;
+	case 'R': return MU_MSG_FLAG_REPLIED;
+	case 'S': return MU_MSG_FLAG_SEEN;
+	case 'T': return MU_MSG_FLAG_TRASHED;
+	case 'D': return MU_MSG_FLAG_DRAFT;
+	case 'F': return MU_MSG_FLAG_FLAGGED;
 		
-		/* NEW OR NOT SEEN */
-	case 'u': return MU_MSG_FLAG_UNREAD;
+	/* NEW OR NOT SEEN */
+	case 'U': return MU_MSG_FLAG_UNREAD;
 		
 	case 'z': return MU_MSG_FLAG_SIGNED;
 	case 'x': return MU_MSG_FLAG_ENCRYPTED;
@@ -75,7 +74,6 @@ mu_msg_flag_from_file_char (char k)
 	switch (k) {
 	case 'D': return MU_MSG_FLAG_DRAFT;
 	case 'F': return MU_MSG_FLAG_FLAGGED;
-	case 'N': return MU_MSG_FLAG_NEW;
 	case 'P': return MU_MSG_FLAG_PASSED;
 	case 'R': return MU_MSG_FLAG_REPLIED;
 	case 'S': return MU_MSG_FLAG_SEEN;
@@ -114,18 +112,20 @@ mu_msg_flag_name (MuMsgFlags flag)
 char
 mu_msg_flag_char (MuMsgFlags flag)
 {
+	g_return_val_if_fail (flag != MU_MSG_FLAG_NONE, 0);
+	
 	switch (flag) {
 		
-	case MU_MSG_FLAG_NEW:		return 'n';
-	case MU_MSG_FLAG_PASSED:	return 'p';
-	case MU_MSG_FLAG_REPLIED:	return 'r';
-	case MU_MSG_FLAG_SEEN:		return 's';
-	case MU_MSG_FLAG_TRASHED:	return 't';
-	case MU_MSG_FLAG_DRAFT:		return 'd';
-	case MU_MSG_FLAG_FLAGGED:	return 'f';
+	case MU_MSG_FLAG_NEW:		return 'N';
+	case MU_MSG_FLAG_PASSED:	return 'P';
+	case MU_MSG_FLAG_REPLIED:	return 'R';
+	case MU_MSG_FLAG_SEEN:		return 'S';
+	case MU_MSG_FLAG_TRASHED:	return 'T';
+	case MU_MSG_FLAG_DRAFT:		return 'D';
+	case MU_MSG_FLAG_FLAGGED:	return 'F';
 
 	/* NEW OR NOT SEEN */
-	case MU_MSG_FLAG_UNREAD:        return 'u';
+	case MU_MSG_FLAG_UNREAD:        return 'U';
 		
 	case MU_MSG_FLAG_SIGNED:	return 'z';
 	case MU_MSG_FLAG_ENCRYPTED:	return 'x';
@@ -162,7 +162,7 @@ mu_msg_flags_from_str (const char* str)
 	
 	for (flags = MU_MSG_FLAG_NONE; str && *str; ++str) {
 		MuMsgFlags flag;
-		if ((flag = mu_msg_flag_char (*str)) == 0) {
+		if ((flag = mu_msg_flag_from_char (*str)) == 0) {
 			flags = 0;
 			break;
 		}
@@ -184,3 +184,5 @@ mu_msg_flags_foreach (MuMsgFlagsForeachFunc func, gpointer user_data)
 		func (ALL_FLAGS[i], user_data);
 }
 
+
+
diff --git a/src/mu-msg-flags.h b/src/mu-msg-flags.h
index 4a2f83f8..cbdf8128 100644
--- a/src/mu-msg-flags.h
+++ b/src/mu-msg-flags.h
@@ -71,21 +71,22 @@ enum _MuMsgFlags {
 	/* "x"->encrypted message */
 	MU_MSG_FLAG_ENCRYPTED   = 1 << 9,
 	/* "a"->message has attachment */
-	MU_MSG_FLAG_HAS_ATTACH  = 1 << 10
+	MU_MSG_FLAG_HAS_ATTACH  = 1 << 10,
 };
 typedef enum _MuMsgFlags MuMsgFlags;
 
+#define MU_MSG_FLAG_INVALID (-1)
+
 
 /**
  * convert the char-per-flag description into a MuMsgFlags value; the
- * characters
- * D=draft,F=flagged,N=new,P=passed,R=replied,S=seen,T=trashed
- * a=has-attachment,s=signed, x=encrypted if any other characters are
- * seen, MU_MSG_FLAG_NONE is returned.
+ * characters D=draft, F=flagged, N=new, P=passed, R=replied, S=seen,
+ * T=trashed a=has-attachment, s=signed, x=encrypted are accepted; if
+ * any other characters are seen, MU_MSG_FLAG_INVALID is returned.
  * 
  * @param str a string
  * 
- * @return a MuMSgFlags value, or MU_MSG_FLAG_UNKNOWN in case of error
+ * @return a MuMSgFlags value, or MU_MSG_FLAG_INVALID in case of error
  */
 MuMsgFlags mu_msg_flags_from_str  (const char* str) G_GNUC_PURE;
 
diff --git a/src/mu-store.cc b/src/mu-store.cc
index caa2a04e..eb57d374 100644
--- a/src/mu-store.cc
+++ b/src/mu-store.cc
@@ -179,7 +179,8 @@ check_version (MuStore *store)
 }
 
 MuStore*
-mu_store_new (const char* xpath, const char *contacts_cache,
+mu_store_new (const char* xpath,
+	      const char *contacts_cache,
 	      GError **err)
 {
 	g_return_val_if_fail (xpath, NULL);
@@ -645,7 +646,7 @@ mu_store_store_msg (MuStore *store, MuMsg *msg, gboolean replace)
 			(msg,
 			 (MuMsgContactForeachFunc)each_contact_info,
 			 &msgdoc);
-			
+		
 		/* add_document is slightly
 		   faster, we can use it when
 		 * we know the document does not exist yet, eg., in
diff --git a/src/mu-store.h b/src/mu-store.h
index f5d123cb..4a3e977d 100644
--- a/src/mu-store.h
+++ b/src/mu-store.h
@@ -41,16 +41,15 @@ typedef struct _MuStore MuStore;
  * 
  * @return a new MuStore object, or NULL in case of error
  */
-MuStore*    mu_store_new     (const char *xpath, const char *ccachepath,
-			      GError **err) G_GNUC_MALLOC G_GNUC_WARN_UNUSED_RESULT;
-
+MuStore*  mu_store_new  (const char *xpath, const char *ccachepath,
+			 GError **err) G_GNUC_MALLOC G_GNUC_WARN_UNUSED_RESULT;
 
 /**
  * destroy the MuStore object and free resources
  * 
  * @param store a valid store, or NULL
  */
-void        mu_store_destroy (MuStore *store);
+void mu_store_destroy (MuStore *store);