diff --git a/doc/mkvmerge.1 b/doc/mkvmerge.1
index a991a5990..2ed6638c7 100644
--- a/doc/mkvmerge.1
+++ b/doc/mkvmerge.1
@@ -103,9 +103,10 @@ ones given with this option have been created.
 \fB\-\-cluster\-length \fR \fIn[ms]\fR
 Put at most \fIn\fR data blocks into each cluster. If the number is
 postfixed with 'ms' then put at most \fIn\fR milliseconds of data into
-each cluster. The maximum length for a cluster is 32767ms. Programs will
+each cluster. The maximum length for a cluster that \fBmkvmerge\fR accepts
+is 60000 blocks and 32000ms; the minimum length is 100ms. Programs will
 only be able to seek to clusters, so creating larger clusters may lead to
-imprecise seeking and/or processing.
+imprecise or slow seeking.
 .TP
 \fB\-\-no\-cues\fR
 Tells \fBmkvmerge\fR not to create and write the cue data which can be compared