add -M doc item
diff --git a/doc/documentation.html b/doc/documentation.html
index 964ffe8..464047b 100644
--- a/doc/documentation.html
+++ b/doc/documentation.html
@@ -218,6 +218,14 @@
 		</TR>
 		<TR>
 			<TD NOWRAP ALIGN="RIGHT" VALIGN="TOP" BGCOLOR="#F4F4CC">
+				-M
+			</TD>
+			<TD>
+				Enable loose mid-side coding (only for stereo streams).  Like <TT>-m</TT> but the encoder adaptively switches between independent and mid-side coding, which is faster but yields less compression.
+			</TD>
+		</TR>
+		<TR>
+			<TD NOWRAP ALIGN="RIGHT" VALIGN="TOP" BGCOLOR="#F4F4CC">
 				-0 .. -9
 			</TD>
 			<TD>
@@ -237,7 +245,7 @@
 				-1
 			</TD>
 			<TD>
-				Synonymous with -l 0 -m
+				Synonymous with -l 0 -M
 			</TD>
 		</TR>
 		<TR>
@@ -269,7 +277,7 @@
 				-5
 			</TD>
 			<TD>
-				Synonymous with -l 8 -m
+				Synonymous with -l 8 -M
 			</TD>
 		</TR>
 		<TR>