diff --git a/man/Compose.man b/man/Compose.man
index 13ba705f..6a8a9668 100644
--- a/man/Compose.man
+++ b/man/Compose.man
@@ -88,16 +88,18 @@ comment at the end of the line:
 .PP
 Each event consists of a specified input keysym, and optional modifier states:
 .RS
-[\fIMODIFIER_LIST\fP] \fB<\fP\fIkeysym\fP\fB>\fP
+[([\fB!\fP] ([\fB~\fP] \fIMODIFIER\fP)...) | \fBNone\fP] \fB<\fP\fIkeysym\fP\fB>\fP
 .RE
 .PP
-Each modifier consists of a specified modifier and a state:
-.RS
-(\fB!\fP \fIMODIFIER\fP ) | \fBNone\fP
-.RE
-Modifiers may be preceded by a
+If the modifier list is preceded by
+.RB \*q "!" \*q
+it must match exactly.
+MODIFIER may be one of Ctrl, Lock, Caps, Shift, Alt or Meta.
+Each modifier may be preceded by a
 .RB \*q "~" \*q
-character to indicate that the modifier must not be present.
+character to indicate that the modifier must not be present. If
+.RB \*q "None" \*q
+is specified, no modifier may be present.
 .PP
 The result specifies a string, keysym, or both, that the X client receives
 as input when the sequence of events is input:
diff --git a/modules/im/ximcp/imLcPrs.c b/modules/im/ximcp/imLcPrs.c
index e9d5f7b7..9bb45ff3 100644
--- a/modules/im/ximcp/imLcPrs.c
+++ b/modules/im/ximcp/imLcPrs.c
@@ -68,8 +68,9 @@ static void parsestringfile(FILE *fp, Xim im, int depth);
  *	COMMENT       ::= "#" {<any character except null or newline>}
  *	LHS           ::= EVENT { EVENT }
  *	EVENT         ::= [MODIFIER_LIST] "<" keysym ">"
- *	MODIFIER_LIST ::= ("!" {MODIFIER} ) | "None"
- *	MODIFIER      ::= ["~"] modifier_name
+ *	MODIFIER_LIST ::= (["!"] {MODIFIER} ) | "None"
+ *	MODIFIER      ::= ["~"] MODIFIER_NAME
+ *	MODIFIER_NAME ::= ("Ctrl"|"Lock"|"Caps"|"Shift"|"Alt"|"Meta")
  *	RHS           ::= ( STRING | keysym | STRING keysym )
  *	STRING        ::= '"' { CHAR } '"'
  *	CHAR          ::= GRAPHIC_CHAR | ESCAPED_CHAR